To increase an amount by 3%, your multiplier would be 1.03 as the multiplier for 3% is 0.03, but because you're increasing the number you need to add the 1. I hope this helps!
Your appropriate choice is ... Yes. When the function f(x) = x3 − 75x + 250 is divided by x + 10, the remainder is zero. Therefore, x + 10 is a factor of f(x) = x3 − 75x + 250.