Despite how open or closed a door is, we perceive the door as a rectangle. Which type of constancy does this demonstrate? A. Size
B. Shape
C. Brightness
D. Color
E. Position

If it’s 15 minutes it would be 159

You're asking in the ap section, so i'll give the ap calculus-style answer. alternatively, you can find the vertex of the parabola and use the "y"-coordinate as the answer.

the maximum height can occur at a critical number, that is, a number  such that  .

the derivative of  can be calculated as follows:



find a value of  that is a zero of the derivative:


this is parabola that is opening downward; we can assume there is a maximum at  .

to find that maximum, calculate  .