Please help me with this two questions:)

Describe the 2 algebraic methods you can use to find the zeros of the function f(t)=-16t^2+400.

Twenty points. suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet

Your food costs are $5,500. your total food sales are $11,000. what percent of your food sales do the food costs represent?