Answer:
A:18 B:19.53
Explanation:
For part A you will have to do 20 * 0.10 ( you get 0.10 by 10/100 or 10 ÷ 100) which is 2, you then have to do 20 - 2 since 2 is the discount amount which is 18.
For part B: You do 8.5 /100 to get 0.085 for tax, you then do 18 * 0.085 = 1.53 which is the tax amount. You add 18.00 + 1.53 and get 19.53.
Hope this helps!
Edit: * = Multiplication