How to solve

A firm production function is $q=KL+L,$ where $q$ is output, $K$ is hours of capital services and $L$ is hours of labor.

a$.$ Does this production function exhibit increasing, constant, or decreasing return to scale?

b$.$ The firm operates so as to minimize its costs and faces a wage of $w=$$$1$ per hour of work and a rental rate of capital of $v=$$$2.$ If it uses $10$ units of $L,$ how many units of $K$ does it use?

c$.$ How many units of oytput does it produce?