Tan 34 = 12/x and then uhm, put 12/tan34 into ur calculator
The question mark is 100. It is a variable if you don't know
The difference (the answer of a subtraction problem) is:
2/7 - 2/5 --> 10/35 - 14/35 = -4/35
The answer sum (the answer of an addition problem) is:
2/7 + 2/5 --> 10/35 + 14/35 = 24/35
Hope this helps.
B is the answer to ur question