A.36小時(shí) B.26小時(shí) C.15小時(shí) D.20小時(shí) E.10小時(shí)
A.50% B.80% C.90% D.70% E.60%
A.80乘以十的九次方/L B.20乘以十的九次方/L C.90乘以十的九次方/L D.60乘以十的九次方/L E.40乘以十的九次方/L