Answer:
C
Step-by-step explanation:
An approximation of an integral is given by:

First, find Δx. Our a = 2 and b = 8:

The left endpoint is modeled with:

And the right endpoint is modeled with:

Since we are using a Left Riemann Sum, we will use the first equation.
Our function is:

Therefore:

By substitution:

Putting it all together:

Thus, our answer is C.
*Note: Not sure why they placed the exponent outside the cosine. Perhaps it was a typo. But C will most likely be the correct answer regardless.
The answer is $12,052.5. youd divide 800 into 1500 then you multiply the answer you get by 6400 then add (1500/100) x 3.5 to get your answer.
The length of a circumference: l=πD
l₁=π×5=5π
l₂=π×15=15π
Then l₂÷l₁=15π÷5π=3 and the answer is B)