Companies frequently borrow money under an arrangement that requires them to make periodic payments of "interest only" and then pay the principal all at once. If Cisco International borrowed $$500,000($identified as loan A$)$ at $10\%$ per year simple interest and another $$500,000($identified as loan B$)$ at $10\%$ per year simple interest and another $$500,000($identified as loan B$)$ at $10\%$ per year compound interest and paid only the interest at the end of each year for $3$ years on both loans, $($a$)$ on which loan did the company pay more interest and $($b$)$ what was the difference in interest paid between the two loans?