Pls help this is a long overdue assignment (Moderators: please stop deleting my questions there is nothing wrong with them)

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?

Asequence is defined recursively using the formula f(n + 1) =f(n) - 5. which sequence could be

If np3 /nc2 = 6, find the value of n