Answer:
A
Step-by-step explanation:
Answer: Level of the liquid dropping at 28.28 inch/second when the liquid is 2 inches deep.
Step-by-step explanation:
Since we have given that
Height = 9 inches
Diameter = 6 inches
Radius = 3 inches
So, 
Volume of cone is given by

By differentiating with respect to time t, we get that

Now, the liquid drips out the bottom of the filter at the constant rate of 4 cubic inches per second, ie 
and h = 2 inches deep.

Hence, level of the liquid dropping at 28.28 inch/second when the liquid is 2 inches deep.
Area of semi circle: you know the radius is 5. 5^2 * pi = 25pi/2 = 12.5pi
For triangle: bh/2 = (10 * 10)/2 = 50
Add them together: 12.5pi + 50
12.5pi = 39.25
39.25 + 50 = 89.25
It’s closest to D
Answer:
E
Step-by-step explanation:
let a, b, c represent the number of students in 6th, 7th, 8th grade
ratio of students : teachers = 28 : 1
There are 82 teachers , so 28 × 82 = 2296 students
Then
a + b + c = 2296 , that is
828 + b + c = 2296 ( subtract 828 from both sides )
b + c = 1468 → E
sin(x) = 2cos(x)
tan(x) = 2
tan⁻¹[tan(x)] = tan⁻¹(2)
x ≈ 63.4
sin(2x) = sin[2(63.4)]
sin(2x) = sin(126.8)
sin(2x) ≈ 0.801