Help me do this i will pick brailest if right and it is 45 points!

Which is the completely factored from of xy^3-x^3y

The quadratic function h(t)=-16.1t^2+150 choose the graph representation

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax