A store has purchased some cola cans of various brands. It purchased 50 cans @ ₹15 per can, 30 cans @ ₹20 per can and 40 cans @ ₹21 per can. Write a Java program to compute how much amount did the store pay.

Identify the operator that gets the highest precedence while evaluating the given expression:

a + b % c * d - e

1. +
2. %
3. -
4. *

Evaluate the expression when x is 4:

x += x++ * ++x % 2;