Guys i need help what's 3+2

Drag the tiles to the correct boxes to complete the pairs. match the cart-coordinates with their corresponding pairs of y-coordinates of the unit circle

If 30 lb of rice and 30 lb of potatoes cost ? $27.60? , and 20 lb of rice and 12 lb of potatoes cost ? $15.04? , how much will 10 lb of rice and 50 lb of potatoes? cost?

Pls the last one and it has to be like number 6