He paid $2.66 in sales tax to find the correct answer you take 22.65-19.99 equals 2.66
Answer:
Rate of Decay = 8%
Step-by-step explanation:
The decay formula is:

Where F is the final value (here, it is given as "Y")
P is the initial value (here, given as 20,000)
r is the rate of decay (what we need to find)
t is the time (given as 2)
Comparing both the equations:

We see that:
1 - r =0.92
We solve for "r":
1 - 0.92 = r
0.08 = r
The rate of decay is 0.08, as a percentage, we need to multiply by 100, so we have:
0.08 * 100 = 8%
Rate of Decay = 8%
A Pentagon has 5 lines of symmetry