Answer:
<h2>
7</h2>
Step-by-step explanation:
Plugged it in the calc!
Hope it helps :)
Assuming n is the number of signers.
7 is 10% of y.
7 = 0.1y
y = 70
n is 80% of y
n = 0.8y
n = 0.8(70)
n = 56
56 signers
3 dimes, 1 nickel
2 dimes, 3 nickels
1 dime, 5 nickels
7 nickels
(don't forget to add in the initial quarter, dime, and nickel)
Parameterize
by

with
and
.
Then the surface element is

and the surface integral is
