砌筑用水泥砂浆应随拌随用，一般在拌制后（）h内用完，如气温高于30℃时，还应缩短1h。
A.2
B.3
C.4
D.5
参考答案：B
Which of the following definitions used in accounting for income taxes is least accurate （）
A. An income tax expense is an expense resulting from current period pretax income and change in deferred taxes.
B. A valuation allowance is a reserve against deferred tax assets based on the likelihood that those assets will not be realized.
C. A deferred tax liability is a balance sheet amount related to the difference between tax expense and taxes payable that is expected to be recovered from future operations
已有定义：int x=3，y=4，z=5，则表达式!(x+y)+z-1&&y+x/2的值是
A．6
B．0
C．2
D．1
