8 is your range, 15-7= 8.
Given:
assessment rate = 51%
tax rate = 53.26 per 1,000
53.26 / 1000 = 0.05326
0.05326 x 100% = 5.326%
Effective tax rate = assessment rate * tax rate
ETR = 51% * 5.326%
ETR = 2.72%
The question is "What's Stella's opportunity cost of working on her serve for an hour?" The rest of the info looks like it's meant to confuse you. They charge $10 an hour. She values an hour of her time at $20. I believe that means she would pay $20. Hope this helps!
$24 because $192divided by $8 is $24
