小明用三根相同的无锈铁钉进行铁制品锈蚀条件的探究(如图),一周后观察.下列说法错误的是( )
先化简再求值
(1)(4a2﹣3a)﹣(1﹣4a+4a2),其中a=﹣2
(2)﹣2(mn﹣3m2)﹣m2﹣5(mn﹣m2)+2mn,其中m=1,n=﹣2.
They didn't continue to climb up the mountain __________ the bad weather.