Ill mark brainllest if right

What is the product of the radical expression. (7-2square root) (8+2 square root)

Which is equivalent to 10/12? options: 10/18 5/6 3/12 9/11

Aheated piece of metal cools according to the function c(x) = (.5)x ? 7, where x is measured in hours. a device is added that aids in cooling according to the function h(x) = ? x ? 2. what will be the temperature of the metal after two hours?