乳化液泵的噪声一般为多少分贝?()
A.合格品94DB
B.一等品92DB
C.二等品90DB
D.优等品91DB
参考答案:A, C, D
She reached the top of the hill and stopped _____on a big rock by the side of the path.
A.to have rested
B.resting
C.to rest
D.rest
激励需求理论的创始人是()
A.马斯洛
B.赫茨伯特
C.弗鲁姆
D.麦克莱兰