Answer:
Step-by-step explanation: pi r^2
so 42/2 equals 21 radius
volume=22/7 x 21^2
v=1385
Answer:
C. 2.0 < t < 2.5
Step-by-step explanation:
time = distance / speed
The circumference of the lake is given by ...
C = πd = 2π miles ≈ 6.28 miles
Then Johanna's time is ...
(6.28 mi)/(3 mi/h) ≈ 2.09 h
This time is in the interval (2, 2.5), so matches choice C.
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<em>Alternate solution</em>
If we take pi to be 3, then this boils down to ...
2×3/3 = 2 . . . hours
Pi is on the order of 5% more than 3, so her time will be on the order of 5% more than 2 hours, or just above 2, but not as great as 2.5 hours. This sort of estimating can get you to the correct answer without a calculator.
Eliminate parentheses using the distributive property.
4806x -3204 +2 = 1360 -544x +90x
5260x = 4562
x = 4562/5260
x = 2281/2630
<h3>The final amount is $ 6881.71</h3>
<em><u>Solution:</u></em>
<em><u>The formula for compound interest, including principal sum, is:</u></em>

Where,
A = the future value of the investment
P = the principal investment amount\
r = the annual interest rate in decimal
n = the number of times that interest is compounded per unit t
t = the time the money is invested
From given,
p = 4000
t = 5

n = 4 ( compounded quarterly )
<em><u>Substituting the values in formula,</u></em>

Thus the final amount is $ 6881.71