单项选择题

After the passage the author will talk about______.

A．the principles of designing lenses
B．techniques of making contact lenses
C．the design of photographic lenses
D．styles of lenses
<上一题 目录 下一题>
热门 试题

单项选择题
Lens design and chess playing are similar in that______.
A．the final goal and the means by which it can be reached are known
B．perfect solutions to a problem can be found
C．any one decision at any point along the way to the goal can bring numerous possible results
D．both A and C
单项选择题
One of the features of REM sleep is that______.
A．there are large slow waves, though rapid for the first few minutes
B．you have the deepest sleep
C．there are no brain waves
D．the brain waves are a little last and the brain becomes a little active
相关试题