Answer:

Step-by-step explanation:
This is horizontal parabola.
It has a directrix at x=-6.
The vertex is (0,0).
The focus is (6,0)
The equation of this parabola is of the form

Where (p,0) is the focus
By comparison, p=6
Therefore the equation of the parabola is

This implies that

4πrsquare= 2πrsquare+2πrh
2πrsquare=2πrh
R=h
So h=16/2=8mm
number of student attend the college are 3150
Step-by-step explanation:
the student teacher ratio is 35:2
let, there are 2x teachers
according to the problem,
2x = 180
or, x = 180/2
= 90
so number of students = 35 X 90 = 3150
Answer:
12m
Step-by-step explanation:
Given that the area of the square DVD case is 144 square cm
Since Area = L²
144 =L²
L = √144
L = 12m
Since the width of the DVD and its case are the same, hence the with of the DVD is also 12m