下面是按―四舍六入五凑偶‖的舍入规则把各有效数字取为4位,正确是的()
A:21.495=21.50,34.465=34.47,6.1305×105=6.131×105
B:8.0130=8.013,1.798501=1.798,0.0028760=0.0029
C:8.0130=8.013,1.798501=1.798,0.0028760=2.876×10-3
D:21.495=21.49,34.465=34.46,6.1305×10^5=6.131×105
出自:电气设备安装工