Answer:
Part A: US$ 17
Part B : US$ 102
Explanation:
1. Let's check all the information given to us to answer the question correctly:
Dinner bill = US$ 85
Tip to the server = 20% of the bill
2. What’s the tip?
20% = 0.2
Tip to the server = 0.2 * 85
Tip to the server = 17
3. What’s the total of the dinner?
Total of the dinner = Dinner bill + Tip to the server
Total of the dinner = 85 + 17
Total of the dinner = 102