A. The answer is : 10%
B. The answer is : 4000
Step-by-step explanation:
(4²-x²)³/²
or,(4+X) (4-X)
Part 1
Use your calculator to have it display
and round that to five decimal places to get 
<h3>Answer: 2.71828</h3>
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Part 2
Plug in x = 5 to get

<h3>Answer: 2.48832</h3>
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Part 3
Now plug in x = 25

<h3>Answer: 2.66584</h3>
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Part 4
Plug in x = 125

<h3>Answer: 2.70749</h3>
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Part 5
As x gets larger, it appears (1+1/x)^x is getting closer and closer to e = 2.71828 since the sequence of answers (from parts 2 through 4) was 2.48832, 2.66584, 2.70749.
Answer: he sent 574 text messages that month
Step-by-step explanation:
Let x represent the number additional text messages that he sent that month.
If his text messaging complain cost $9 for the first 550 text messages and .20 for additional text messages, it means that the total cost of sending x text messages for a month would be
9 + 0.2(x - 550)
If Tj owes $13.80 for text messaging in the month of March, it means that
9 + 0.2(x - 550) = 13.8
0.2x - 110 = 13.8 - 9
0.2x = 13.8 - 9 + 110
0.2x = 114.8
x = 118.8/0.2
x = 574