Answer:
20 because 40 is a positive and spent is negative
Step-by-step explanation:
We're looking for a scalar function
such that
. That is,


Integrate the first equation with respect to
:

Differentiate with respect to
:

Integrate with respect to
:

So
is indeed conservative with the scalar potential function

where
is an arbitrary constant.
The awnser to this question is 14.1
For this, we can set up a proportion.
Their aim was 15000, so if they raised 100% of their goal, they wouldve raised exactly 15000.
They raised 557%, so how much did they make?
Proportion:
$15000 100%
$x 557%
Our expression would be x=$15000*557% divided by 100%, which would be $83550, so... a lot of money.
(we did an “x” formation with the proportion, ie “connected” x with 100, and “connected” 15k and 557. The number connecting to x is what we divide the equation by, and the other two are multiplied and then divided by the first number connecting to x. Otherwise we couldve calculated 557% of 15000 and gotten the same result. Whichever way is easier for you :) )
Number of strings =

= 21 x 21 x 21 x 21 x 21 x 5 = 20 420 505
Answer: 20 420 505