The task is to generate the correct answer for a given math problem.

[EX Q]: Problem: the area of a triangle is with base 12 m and height 5 m ?
[EX A]: 30 m 2

[EX Q]: Problem: the average weight of 8 person ' s increases by 3 kg when a new person comes in place of one of them weighing 70 kg . what might be the weight of the new person ?
[EX A]: 94 kg

[EX Q]: Problem: elvin ' s monthly telephone bill is the sum of the charge for the calls he made during the month and a fixed monthly charge for internet service . elvin ' s total telephone bill for january was $ 46 and elvin ' s total telephone bill for february was 76 $ . if elvin ' s charge for the calls he made in february was twice the charge for the calls he made in january , what is elvin ' s fixed monthly charge for internet service ?
[EX A]:
$ 16