某县有人口10万人，1997年因各种疾病死亡1000人。该年共发生结核300人，原有结核400人，1997年共有60人死于结核

结核的病死率为

A:60/300 B:60/400 C:60/700 D:60/1000 E:60/10万

男性，35岁，体重60kg。双上肢,躯干,双臀,会阴部被硫酸烧伤。

患者的烧伤面积为

A:25% B:40% C:50% D:60% E:30%

患者周某，男性，64岁，上颌全牙列缺失，散在骨尖。下颌多数牙缺失，仅余。近中舌侧倾斜，牙槽嵴丰满，猞间距离正常

宜用哪种卡环

A:圈形卡 B:联合卡 C:回力卡 D:杆形卡 E:对半卡

食品中有毒物质限量的标准，通常是根据危险性分析的基本原理并按照相应的程序来制定。以某农药为例，在这个过程中，如果动物最大无作用剂量已确定为60mg／(kg·bw)

体重60公斤的成年人每日最高摄入该农药的量(mg)应不超过

A:60 B:6 C:3．6 D:36 E:360

根据《药品广告审查办法》，异地发布药品广告在发布地的程序要求是(　)。

A:向所在省级工商管理部门办理备案 B:向所在省级工商管理部门申请并取得药品广告批准文号 C:向所在省级药品监督管理部门申请并取得药品广告批准文号 D:向所在省级药品监督管理部门办理备案

Both Boeing and Airbus have trumpeted the efficiency of their newest aircraft, the 787 and A350 respectively. Their clever designs and lightweight composites certainly make a difference. But a group of researchers at Stanford University, led by Ilan Kroo, has suggested that airlines could take a more naturalistic approach to cutting jet-fuel use, and it would not require them to buy new aircraft.
The answer, says Dr. Kroo, lies with birds. Since 1914, and a seminal paper by a German researcher called Carl Wieselsberger, scientists have known that birds flying in formation—a V-shape, echelon or otherwise—expend less energy. The air flowing over a bird’s wings curls upwards behind the wingtips, a phenomenon known as upwash. Other birds flying in the upwash experience reduced drag, and spend less energy propelling themselves. Peter Lissaman, an aeronautics expert who was formerly at Caltech and the University of Southern California, has suggested that a formation of 25 birds might enjoy a range increase of 71%.
When applied to aircraft, the principles are not substantially different. Dr. Kroo and his team modeled what would happen if three passenger jets departing from Los Angeles, San Francisco and Las Vegas were to rendezvous over Utah, assume an inverted V-formation, occasionally swap places so all could have a turn in the most favourable positions, and proceed to London. They found that the aircraft consumed as much as 15% less fuel (with a concomitant reduction in carbon-dioxide output). Nitrogen-oxide emissions during the cruising portions of the flight fell by around a quarter.
There are, of course, kinks to be worked out. One consideration is safety, or at least the perception of it. Would passengers feel comfortable travelling in convoy’ Dr. Kroo points out that the aircraft could he separated by several nautical miles, and would not be in the unnervingly easy groupings favoured by display teams like the Red Arrows. A passenger peering out of the window might not even see the other planes. Whether the separation distances involved would satisfy air-traffic-control regulations is another matter, although a working group at the International Civil Aviation Organization has included the possibility of formation flying in a blueprint for new operational guidelines.
It remains to be seen how weather conditions affect the air flows that make formation flight more efficient. In zones of increased turbulence, the planes’ wakes will decay more quickly and the effect will diminish. Dr. Kmo says this is one of the areas his team will investigate further. It might also he hard for airlines to coordinate the departure times and destinations of passenger aircraft in a way that would allow them to gain from formation flight. Cargo aircraft, in contrast, might be easier to reschedule, as might routine military flights.
As it happens, American’s armed forces are on the ease already. Earlier this year the country’s Defense Advanced Research Projects Agency announced plans to pay Boeing to investigate formation flight, though the programme has yet to begin. There are reports that some military aircraft flew in formation when they were low on fuel during the Second World War, hut Dr. Lissaman says they are apocryphal. "My father was an RAF pilot and my cousin the skipper of a Lancaster lost over Berlin," he adds. So he should know.

A:Three passengers were in the most favourable positions during the experiment. B:15% less fuel reduction in carbon-dioxide output and nitrogen-oxide emissions during flying. C:Kroo and his team conducted their experiments in Los Angeles, San Francisco, Las Vegas, Utah and London. D:Air crafts can occasionally swap places to turn in the most favourable positions as well as birds.

Both Boeing and Airbus have trumpeted the efficiency of their newest aircraft, the 787 and A350 respectively. Their clever designs and lightweight composites certainly make a difference. But a group of researchers at Stanford University, led by Ilan Kroo, has suggested that airlines could take a more naturalistic approach to cutting jet-fuel use, and it would not require them to buy new aircraft.
The answer, says Dr. Kroo, lies with birds. Since 1914, and a seminal paper by a German researcher called Carl Wieselsberger, scientists have known that birds flying in formation—a V-shape, echelon or otherwise—expend less energy. The air flowing over a bird’s wings curls upwards behind the wingtips, a phenomenon known as upwash. Other birds flying in the upwash experience reduced drag, and spend less energy propelling themselves. Peter Lissaman, an aeronautics expert who was formerly at Caltech and the University of Southern California, has suggested that a formation of 25 birds might enjoy a range increase of 71%.
When applied to aircraft, the principles are not substantially different. Dr. Kroo and his team modeled what would happen if three passenger jets departing from Los Angeles, San Francisco and Las Vegas were to rendezvous over Utah, assume an inverted V-formation, occasionally swap places so all could have a turn in the most favourable positions, and proceed to London. They found that the aircraft consumed as much as 15% less fuel (with a concomitant reduction in carbon-dioxide output). Nitrogen-oxide emissions during the cruising portions of the flight fell by around a quarter.
There are, of course, kinks to be worked out. One consideration is safety, or at least the perception of it. Would passengers feel comfortable travelling in convoy’ Dr. Kroo points out that the aircraft could he separated by several nautical miles, and would not be in the unnervingly easy groupings favoured by display teams like the Red Arrows. A passenger peering out of the window might not even see the other planes. Whether the separation distances involved would satisfy air-traffic-control regulations is another matter, although a working group at the International Civil Aviation Organization has included the possibility of formation flying in a blueprint for new operational guidelines.
It remains to be seen how weather conditions affect the air flows that make formation flight more efficient. In zones of increased turbulence, the planes’ wakes will decay more quickly and the effect will diminish. Dr. Kmo says this is one of the areas his team will investigate further. It might also he hard for airlines to coordinate the departure times and destinations of passenger aircraft in a way that would allow them to gain from formation flight. Cargo aircraft, in contrast, might be easier to reschedule, as might routine military flights.
As it happens, American’s armed forces are on the ease already. Earlier this year the country’s Defense Advanced Research Projects Agency announced plans to pay Boeing to investigate formation flight, though the programme has yet to begin. There are reports that some military aircraft flew in formation when they were low on fuel during the Second World War, hut Dr. Lissaman says they are apocryphal. "My father was an RAF pilot and my cousin the skipper of a Lancaster lost over Berlin," he adds. So he should know.
Which of the following can support "the principles are not substantially different"

A:Three passengers were in the most favourable positions during the experiment. B:15% less fuel reduction in carbon-dioxide output and nitrogen-oxide emissions during flying. C:Kroo and his team conducted their experiments in Los Angeles, San Francisco, Las Vegas, Utah and London. D:Air crafts can occasionally swap places to turn in the most favourable positions as well as birds.

Both Boeing and Airbus have trumpeted the efficiency of their newest aircraft, the 787 and A350 respectively. Their clever designs and lightweight composites certainly make a difference. But a group of researchers at Stanford University, led by Ilan Kroo, has suggested that airlines could take a more naturalistic approach to cutting jet-fuel use, and it would not require them to buy new aircraft.
The answer, says Dr. Kroo, lies with birds. Since 1914, and a seminal paper by a German researcher called Carl Wieselsberger, scientists have known that birds flying in formation—a V-shape, echelon or otherwise—expend less energy. The air flowing over a bird’s wings curls upwards behind the wingtips, a phenomenon known as upwash. Other birds flying in the upwash experience reduced drag, and spend less energy propelling themselves. Peter Lissaman, an aeronautics expert who was formerly at Caltech and the University of Southern California, has suggested that a formation of 25 birds might enjoy a range increase of 71%.
When applied to aircraft, the principles are not substantially different. Dr. Kroo and his team modeled what would happen if three passenger jets departing from Los Angeles, San Francisco and Las Vegas were to rendezvous over Utah, assume an inverted V-formation, occasionally swap places so all could have a turn in the most favourable positions, and proceed to London. They found that the aircraft consumed as much as 15% less fuel (with a concomitant reduction in carbon-dioxide output). Nitrogen-oxide emissions during the cruising portions of the flight fell by around a quarter.
There are, of course, kinks to be worked out. One consideration is safety, or at least the perception of it. Would passengers feel comfortable travelling in convoy’ Dr. Kroo points out that the aircraft could he separated by several nautical miles, and would not be in the unnervingly easy groupings favoured by display teams like the Red Arrows. A passenger peering out of the window might not even see the other planes. Whether the separation distances involved would satisfy air-traffic-control regulations is another matter, although a working group at the International Civil Aviation Organization has included the possibility of formation flying in a blueprint for new operational guidelines.
It remains to be seen how weather conditions affect the air flows that make formation flight more efficient. In zones of increased turbulence, the planes’ wakes will decay more quickly and the effect will diminish. Dr. Kmo says this is one of the areas his team will investigate further. It might also he hard for airlines to coordinate the departure times and destinations of passenger aircraft in a way that would allow them to gain from formation flight. Cargo aircraft, in contrast, might be easier to reschedule, as might routine military flights.
As it happens, American’s armed forces are on the ease already. Earlier this year the country’s Defense Advanced Research Projects Agency announced plans to pay Boeing to investigate formation flight, though the programme has yet to begin. There are reports that some military aircraft flew in formation when they were low on fuel during the Second World War, hut Dr. Lissaman says they are apocryphal. "My father was an RAF pilot and my cousin the skipper of a Lancaster lost over Berlin," he adds. So he should know.
Which of the following can support "the principles are not substantially different"

A:Three passengers were in the most favourable positions during the experiment. B:15% less fuel reduction in carbon-dioxide output and nitrogen-oxide emissions during flying. C:Kroo and his team conducted their experiments in Los Angeles, San Francisco, Las Vegas, Utah and London. D:Air crafts can occasionally swap places to turn in the most favourable positions as well as birds.