Maximum Height of a Quadratic Function

Rachel is analyzing the growth of a certain plant species under different lighting conditions. She models the height of the plants (in centimeters) after $t$ days using the quadratic function given by:

$$ h(t) = -2t^2 + 30t + 10 $$

Rachel wants to determine the maximum height that the plants can reach. To find this height, she needs to calculate the value of $h(t)$ at the vertex of the parabola defined by the function.

What is the maximum height (in centimeters) of the plants? Enter your answer as a decimal in the grid below.