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

Problem: what is the range of all the roots of | x ^ 2 - 4 | = x ?
3

Problem: a train 300 m long is running with a speed of 68 kmph . in what time will it pass a man who is running at 8 kmph in the same direction in which the train is going ?
18 sec .

Problem: given that p is a positive even integer with a positive units digit , if the units digit of p ^ 3 minus the units digit of p ^ 2 is equal to 0 , what is the units digit of p + 4 ?

10