—Amy , I would like your uncle to help me repair the computer.

—Sorry, he _____help you today . He won’t come back until tomorrow.

A．shouldn’t

B．may not

C．can’t

D．mustn’t

计算可重复系数进行整个量表质量考核的是（）量表。

A.总和

B.累计

C.定距

D.定比