疏散用应急照明，其最低照度不应低于( )lux。
A．0.12
B．0.31
C．0.51
D．0.65
参考答案：C
当a=（ ）时，x2-4ax+4可以写成两数和或差的平方。
--Would you like to see a film with us tonight ?
--- I’d like to. But I can’t ______ the time because I have to finish my composition.
A．afford
B．pass
C．take
D．spend
