题目

Sir, do you have anything _________ this afternoon? If there is nothing to do, I wonder if I can ask for a leave． A . typing B . typed C . to type D . to be typed 答案：D已知圆锥的底面半径为1cm，母线长为3cm，则圆锥的侧面积是（　　）A．6cm2B．3πcm2C．6πcm2D．32πcm2