单项式3x2yn-1z是关于x、y、z的五次单项式，则n=______．
由单项式的定义可知，2+n-1+1=5，解得n=3．
Picasso’s paintings, which are among the greatest, are reported _______ in Chengdu right now.
A．to show
B．to be shown
C．to be being shown
D．to have been shown
一个平行四边形的面积是70平方厘米，底是10厘米，高是______．
