石子压碎指标检验中试样质量为100g,试样筛余量为80g,则压碎指标值为( )。
A.10
B.80
C.20
D.30
参考答案:C
吹气和哈气都是从人口中出来的气,夏天用口“吹气”能使开水变凉,是因为吹气加快了水面上方 _____ ,从而加快了开水的 ____ ,而 ____ 吸热;冬天对着手“哈气”使手暖和,是因为哈出的水蒸气遇冷 ____ ,使手的温度升高.
The government has taken measures to ________ the high prices of daily goods to keep the market
stable.[ ]
A. take down
B. bring down
C. hand down
D. tear down