Choose the correct correspondence C S R T

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

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?

My hour hand points between the 8 and the 9 in 35 minutes it will be the next hour. what time is it ?