题目

Great changes ____________ in my hometown in the past few years. A have taken place. B. took placeC. have been happened D. were taken place 答案：A 解析: 略利用天平、水、刻度尺、水彩笔、烧杯把一只均匀的圆柱形的茶杯制作成量程100ml、分度值5ml的量筒．写出主要的步骤、在茶杯上画出刻度．