JPEG压缩具备以下特点（）。
A.易于传输
B.不失真
C.色彩的信息保留较好
D.易于控制调整
参考答案：A, C, D
—Long time no see．Haven't you graduated from college?
—Yes．I____business management for 4 years in Beijing．
A．study
B．have studied
C．studied
D．am studying
两人以上在机车上作业时，应注意什么？
