肾岩好发年龄为:
A.10~20B.20~30C.20~40D.40~60E.60岁以上
参考答案:D
Maintenance of charts and nautical publications up to date is a statutory requirement under the()Convention.
A.STCW
B.MARPOL
C.SOLAS
D.ISM
配料的精确性在很大程度上取决于所采用的配料方法,目前,配料方法有()配料和()配料。