Function domain word problems

Mason stands on the $5^{\text{th}}$‍ step of a vertical ladder. The ladder has $15$‍ steps, and the height difference between consecutive steps is $0.5\text{ m}$‍.

$h(n)$‍ models the height above the ground of Mason's feet (in $\text{m}$‍) after moving $n$‍ steps (if Mason went down the ladder, $n$‍ is negative.)