Could someone explain how to solve this? !

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?

What is true about the dilation? it is a reduction with a scale factor between 0 and 1. it is a reduction with a scale factor greater than 1. it is an enlargement with a scale factor between 0 and 1. it is an enlargement with a scale factor greater than 1.

Average acceleration: i have no idea how to do this.