【单选题】下列叙述中不具状态函数特征的是( )
B.
系统变化时,状态函数的改变值只由系统的初终态决定
【单选题】Total output in an economy increases when each person specializes becausea.there is less competition for the same resources.b.each person spends more time producing that product in which he or she ha...
【判断题】SPF 是防晒系数(又叫防晒系指数,Sun Protection Factor)的英文缩写,表明防晒用品所能发挥的防晒效能的高低。
【单选题】灌砂法测定压实度试验,灌砂过程中,储砂筒内砂尚在下流时即关闭开关,压实度结果将比正常结果( )。