In the given equation \( y = -16t^2 + 40 \), \( y \) represents the height of the egg contraption at time \( t \), where \( t \) is measured in seconds.
When \( t = 0 \) (the moment the contraption is dropped), the equation gives:
\[ y = -16(0)^2 + 40 = 40 \text{ feet} \]
Thus, the height of the school’s roof is 40 feet.
So, the correct interpretation is:
40 feet.