Answer:
$94.81
Step-by-step explanation:
the selling price (before discount 20%) =
$98.60 ÷ (100-20)%
= $98.60 ÷ 0.8 = $123.25
the store paid for the clarinet =
$123.25 ÷ (100+30)%
= $123.25 ÷ 1.3 = $ 94.81
Rule of 90 clockwise rotation
(x,y) --->(y, -x)
C(2,7) ,90 clockwise rotation will be C'(7, -2)
Answer: second option (7, -2)