Explosive devices used in mining operations produce nearly circular craters when detonated. The radii of these craters are exponentially distributed with mean feet. Find the mean and variance of the areas produced by these explosive devices.

What is the factored form of the following expressions? d^2 – 13d + 36

45% of the trees in a park are apple trees. there are 27 apple trees in the park. how many trees are in the park in all?

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?