the unit digit in the product 1256 * 6785 * 4587 * 9785 is ?
"unit digit in the given product = unit digit in 6 * 5 * 7 * 5 = 0 answer is a"
subtract(multiply(multiply(multiply(1256, 6785), 4587), 9785), subtract(multiply(multiply(multiply(1256, 6785), 4587), 9785), add(const_4, const_4)))