在一个平面上拉毛时，应避免中断留槎，以确保达到色泽一致不露底。
参考答案：对
A little learning is a dangerous thing, for you might as well not know a thing () know it only imperfectly.
A. that
B. as
C. than
D. but
水准测量每公里的高差中误差的决定因素是（）。①照准误差②外界环境误差③视线i角误差④人为误差⑤读数误差⑥水准尺刻划误差
A.①③④⑤
B.①③⑤⑥
C.②③④⑤
D.①②③⑥
