The way to do this is to set up a 30 degree angle in a coordinate plane in the first quadrant. I say the first quadrant since the first quadrant goes from 0 to 90 degrees and 30 falls right in that interval. Using the positive x-axis as the initial ray of the 30 degree angle and the terminal ray of the angle as the hypotenuse of a right triangle, if we drop a height from the end of the terminal ray to the x-axis we have formed said right triangle. The angle at the origin is the 30 degree angle. According to the Pythagorean triple for a 30-60-90 triangle, the side across from the 30 degree angle measures 1, which is the height of our triangle. The side across from the 60 degree angle is square root of 3, which is the base of our triangle, and the hypotenuse is 2. The cos identity is the ratio that utilizes the side adjacent to the reference angle over the hypotenuse, which for us is

. That's the third choice down. Finding an "exact" value means that they want you to NOT express your answer in decimal form.
I will not go to school tomorrow
The earth is not the center of the solar system
Angle A and angle B are not congruent
The money you gave me was not enough
She is enjoying her time
I did bring the key
I hope this helps.
The number 8 would be its simplest form.<span />
9514 1404 393
Answer:
8000π mm^3/s ≈ 25,133 mm^3/s
Step-by-step explanation:
The rate of change of volume is found by differentiating the volume formula with respect to time.
V = 4/3πr^3
V' = 4πr^2·r'
For the given numbers, this is ...
V' = 4π(20 mm)^2·(5 mm/s) = 8000π mm^3/s ≈ 25,133 mm^3/s
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<em>Additional comment</em>
By comparing the derivative to the area formula for a sphere, you see that the rate of change of volume is the product of the area and the rate of change of radius. This sort of relationship will be seen for a number of different shapes.
40! When you add all four angles of a quadrilateral together, you will always end up with 360. So, 360-75-120-125=40 :) have a great day!