F(x)=-x^2+8x-20 find the min/max value

Arectangular prism is 3 meters long, 6 meters wide, and has a height of 9 meters. what is its surface area?

Question 3 of 30 paul buys fruit to make smoothies. he buys 3.78 pounds of apples, 2.12 pounds of peaches, and 4.45 pounds of oranges. paul rounds each weight to the nearest tenth of a pound. about how many pounds of fruit did paul buy? (a) 10.5 pounds (b) 10.2 pounds (c) 10.4 pounds (d) 10.0 pounds 30 points

Can somebody me out with this question