I think the answer is -4x^-11x+13
Answer:
$0.21
Step-by-step explanation:
We can set up a proportion. Say x is the cost of 1 wristband:

Now, we cross multiply:
25x = 5.25
Solving for x, we see that x = 0.21.
Thus, the answer is $0.21.
Multiply by a across the formula
Same would need to get at least a 95% on the next test, if he would like to receive a total average of an 80%