Please help, and i will mark you BRAINLIEST
Solve:
A. 27
B. 343
C. 729
D. 216

729

Step-by-step explanation:

9 x 9 = 81

81 x 9 = 729

$20.5

Step-by-step explanation:

Let x  denotes the amount for total bill.

We are given that ,  Sierra left $4.50 as a tip for a waiter.

This was 18% of the bill before the tip.

We can write 18% = 0.18. [To convert percent into decimal we divide it by 100.]

Then, the tip amount = 0.18 x Total bill

So, the total bill amount = $25

Hence, her total bill before the tip= Total bill amount - Tip amount

= $25- $4.50=$20.5

Thus ,her total bill before the tip= $20.5