Answer:

Step-by-step explanation:
In rectangle ABCD, AB = 6, BC = 8, and DE = DF.
ΔDEF is one-fourth the area of rectangle ABCD.
We want to determine the length of EF.
First, we can find the area of the rectangle. Since the length AB and width BC measures 6 by 8, the area of the rectangle is:

The area of the triangle is 1/4 of this. Therefore:

The area of a triangle is half of its base times its height. The base and height of the triangle is DE and DF. Therefore:

Since DE = DF:

Thus:

Since ABCD is a rectangle, ∠D is a right angle. Then by the Pythagorean Theorem:

Therefore:

Square:

Add:

And finally, we can take the square root of both sides:

Answer:
12375
Step-by-step explanation:
one rotation: 495
25 rotations x 495 seconds
12375 seconds
Number 6 is c because 99/108 to the smallest form is 11/12
Basically if you have an exponent at the end of a 10,

, then in the end the extended notation is going to have 7 zeros. So it'll be 10000000. Then you multiply whats in the rest of the equation together. There's the beginning :) I hope it helps.