The answer for the first question is 1

You have to separate 2^32 -1 to (2^16+1)(2^16-1)

then you can cancel (2^16-1) from the numerator and denominator 

Repeat this process again until it becomes 1/1

Therefore the answer is 1

The second answer is 48

As per the pattern, a remains 4 each time 

As per the pattern, 8 is being added to the second term each time

As per the pattern, a multiple of 8 is being added to the third term each time 

As per the pattern, a multiple of 8 is being added to the fourth term each time

Hence:-

A=4

B=44

C=118

D=126 

B+D-A-C

44 +126 -4 -118

=48