Working with a Piecewise Function

A cell phone company uses the function below to determine the cost, $C,$ in dollars for $g$ gigabytes of data transfer.

$$C\left(g\right)=\{\begin{array}{ccc}25& \text{if}& 0<g<2\\ 25+10\left(g-2\right)& \text{if}& g\ge 2\end{array}$$

Find the cost of using 1.5 gigabytes of data and the cost of using 4 gigabytes of data.

OpenStax, Algebra and Trigonometry 2e · §3.2 Domain and Range · Example 11