total charge = days late * fine
3.77 = 13*fine
divide by 13 on each side
3.77 /13 = fine
.29
The charge is $.29 per day
Step-by-step explanation:
A left Riemann sum approximates a definite integral as:

Given ∫₂⁸ cos(x²) dx:
a = 2, b = 8, and f(x) = cos(x²)
Therefore, Δx = 6/n and x = 2 + (6/n) (k − 1).
Plugging into the sum:
∑₁ⁿ cos((2 + (6/n) (k − 1))²) (6/n)
Therefore, the answer is C. Notice that answer D would be a right Riemann sum rather than a left (uses k instead of k−1).
Answer:
River C is: 2,965 miles long.
River D is: 2,565 miles long.
Step-by-step explanation:

Have a great day! ^^
Both of them are the first answer choice