1.Would you please_________the two pieces of wood together s

1.Would you please_________the two pieces of wood together so that it is long enough?
A.destroy
B.join
C.replace
D.exchange
2.首字母填空：
The day of the test a______at last.Jane couldn't answer many of the questions in the exam.
3.已知直线y=(k-3)x+5-2k与直线y=4x-3没有交点,且经过点（2,a).求a的值.
4.见图.
.