患者，女，10岁，替牙，上颁发育正常，前牙与之间开，有舌前伸习惯，无牙列拥挤，上前牙唇倾。

为判断病人错类型应该拍摄

A:牙片 B:咬片 C:X线头影测量 D:胸片 E:手腕骨片

患者，女，10岁，替牙，上颁发育正常，前牙与之间开，有舌前伸习惯，无牙列拥挤，上前牙唇倾。

患者错的主要原因是

A:佝偻病 B:遗传 C:骨性错 D:牙性错 E:口腔不良习惯

EM是

A:化学文摘 B:医学文摘 C:医学索引 D:国际药学文摘 E:中国药学文摘

Ep＝（）Em

A:2 B:1/π C:2/π D:3/π

0，112，223，334，445，( )

A:5 B:16 C:667 D:556

Do the suffixes -able in workable, -ness in workableness change the word class of the words to which they are attached Are they bound morphemes or free morphemes Inflections or derivations

The suffixes -able in workable and -ness in workableness have changed the word class of the words to which they are attached．They are bound morphemes，though -able is both a free and bound morpheme．They are derivational morphemes．

已知测站点高程为H_A时，则立尺点的高程
H_B=H_A+h=H_A+i-l式中h为两点高差、i为仪器高、l为目标高上式称视准轴水平时的视距测量计算式。( )

设变量$x,y$满足约束条件$\left\{\begin{array}{l}x+y-2⩾0\\ x-y-2⩽0\\ y⩾1\end{array}\right.$,则目标函数$z=x+2y$的最小值为$($$$$)$

A: $2$$$ B: $3$$$ C: $4$$$ D: $5$

在平行六面体$ABCD$-$A_1{B}_1{C}_1{D}_1$中，设$\overrightarrow{A{C}_1}$=$x\overrightarrow{AB}$+$2y\overrightarrow{BC}$+$3z\overrightarrow{C{C}_1}$，则$x+y+z$等于$($$$$)$

A: 1 B: $\frac{2}{3}$$$ C: $\frac{5}{6}$$$ D: $\frac{11}{6}$