A.4.8-5.2 B.5.0-5.4 C.5.2-5.6 D.5.4-5.8
A.1次/2h B.1次/1h C.1次/4h D.1次/0.5h
A.4+5+2 B.4+5+1 C.5+5+4 D.4+5+5