The volume of a Cylinder is:

the base is a circle, so

replacing

now we have the values

The function
exists in a parabola.
The axis of symmetry of a parabola exists at the midpoint between the two real roots.
The roots exist the solutions of H(t) = 0
To estimate the roots equation exists 
Factor t(-16t + 64) = 0
t = 0 and -16t + 64 =0
-16t + 64 = 0
t = 64 / 16 = 4
t = 4
Then the two roots are t = 0 and t = 4, and the axis of symmetry exists
t = (0+4)/2 = 4/2 = 2
<h3>How to estimate the axis of symmetry?</h3>
The axis of symmetry exists at t = 2.
It represents the time at which the ball is at the higher point, the maximum height.
You can find the maximum height replacing t = 2 in the function H(t)

= 64 feet.
And you can also deduce that the second part of the flight will take 2 seconds, for a total flight time of 4 seconds.
To learn more axis of symmetry refers to:
brainly.com/question/21191648
#SPJ4
Answer: There were 89 retail stores in 1997.
Step-by-step explanation:
Hi, to answer this question, first, we have to calculate the number of years since 1990(x).
1997-1990 = 7 years
Now, we simply substitute x=7 (years) in the equation given
y=11x+12
y=11(7)+12
y=77+12
y = 89 retail stores
There were 89 retail stores in 1997.
Feel free to ask for more if needed or if you did not understand something.
Step-by-step explanation:
a) 3x + 5y = 8
4x - 3y = 1
• using the elimination method:
3x + 5y = 8 (×4)
4x -3y = 1 (×3)
12x + 20y = 32
12x -9y = 3
subract 12x from both equation:
20y - - 9y= 32 -3
20y +9y = 29
29y= 29
y= 29/29
y= 1
- substituting y= 1 in :
4x - 3y= 1
4x - 3(1) = 1
4x -3 = 1
4x = 1 + 3
x = 4/4
x= 1
b) 6p+ 4q = 20
5p - 2q = 6
• using the elimination method:
6p + 4q = 20
5p - 2q = 6 (×2)
6p + 4q = 20
10p - 4q = 12
add 4q + -4q to eliminate q.
6p+ 10p = 20+12
16p = 32
p = 32/ 16
p = 2
- subtituting p = 2 in :
5p - 2q = 6
5(2) -2q =6
10 -2q = 6
-2q = 6 - 10
q = -4 / -2
q = 2
hope this helps you,
-s.