A.增大
B.减小
C.不变
D.不能确定
[单选题]A.B.C.D.E.
[单选题]A.28.14B.31C.34.25D.45.51
[单选题]A.0B.1C.2D.3
[单选题]A.150B.160C.180D.200
[单选题]A.增大B.减小C.不变D.不能确定