ANSWER
to the nearest hundredth.
EXPLANATION
We have the equation,

Which can be rewritten as

The question demands the use of the quadratic formula.
Comparing this to the general quadratic equation;


The quadratic formula is given by;

We now substitute all the values in to the formula;

We simplify to obtain;


We now split the plus or minus sign to obtain;

This implies that;

Or

This will evaluate to;

Hence, the positive solution rounded to the nearest hundredth is

To find h(6), we must plug in 6 into the function.
h(x) = x^2 - 2x - 5
h(6) = 6^2 - 2(6) - 5
= 36 - 12 - 5
= 36 - 17 = 19
Take any of the valid pairs of points, use the formula
rate of change = (y2-y1)/(x2-x1)
Say we use P1=(0,21.4), P2=(3,19)
x1=0, y1=21.4
x2=3, y2=19
Rate of change = (21.4-19)/(0-3)=2.4/(-3) = -0.8 sq. ft/in of liquid
Answer: B) False
A counter-example would be the cubic polynomial y = x^3 which doesn't have a max or a min. The graph stretches forever in both directions (up and down) indicating that the range is the set of all real numbers.