23、The economic heart (A)of Canada, Ontario accounts for (B) more than 40 percentage (C) of the nation's productive capacity(D).
是不是前面是百分数，后面的CAPACITY就应该是复数？
13、The distinguishing feature of a fluid, in contrast to a solid, is the ease
A) that a deformed fluid
B) to deform a fluid
C) when a fluid that is deformed
D) with which a fluid may be deformed
B）错在哪里呢？ | 
