Answer:
1.
a. 2.75 seconds
b. 169 feet
2. x - 3 is a factor
Other factors: x + 2, 2x + 1, 3x - 4
3. Real zeros:

Complex zeros:

Explanation:
1. Given equation of parabola

a) The rocket reaches its maximum height at the vertex of parabola. Find t-coordinate of the vertex:

b) The maximum height is s-coordinate of the vertex. Find it:

2. For x – 3 to be a factor of
the Factor Theorem says that x = 3 must be a zero of f(x). Check it (whether f(3)=0):

So, x = 3 is zero of the function f(x) and x - 3 is the factor of the function f(x). Rewrite the function as follows:

3.
is a zero of the function
then

Find the discriminant of the quadratic polynomial


This expression has no more real zeros (the discriminant is less than 0), it has two complex zeros:
