Decompose the terms in the sum as

so there are 20 terms in the sum. Then our sum simplifies to

Now, if

we can reverse the order of terms to get the same sum,

so that doubling up the sum gives

So, our sum evaluates to

Answer:
b there is no soulotion...
Answer:
sorry,
I think yr questions is incomplete.
Answer:
Measure of the arc = 360-74° = 286°
An arc measure is the measure of an angle that the arc creates in the center of a circle.
A)
we will write the equation

B) x=10, we just replace the x and solve y

the number of cases of water ir 15