Answer:
80
Explanation:
541A3 is a multiple of 3 when the sum of the digit is a multiple of 3 so the sum of the 4 given number is 5+4+1+3=13. but we need it to be a multiple of 3 so we add 2 so A is 2. Using similar logic B=5 and C=8 so the product of A B and C is 2*5*8=80