Which of the following device should get higher priority on assigning interrupts?

Which of the following is true?

Let A be a two dimensional array declared as follows:
A : array [ 1... 10] [1... 15] of integer;
Assuming that each integer takes one memory locations the array is stored in row-major order and the first element of the array is stored at location 100, what is the address of the element A[i] [j]?

Compute the post fix equivalent of the following expression. 3 * log(x+1) - a/2