【2015贵州六盘水】23.You are supposed to type quickly when talking with others on QQ.
A:must
B:can
C:should
D:would
下列函数(1)y=πx(2)y=﹣2x+1(3)y=1x(4)y=2﹣1﹣3x(5)y=x2﹣1中,是一次函数的有( )
Mocky ____ (change) the recipe.