Answer:
V = 1436.76
Step-by-step explanation:
<u>Formula:</u>
V = 4/3πr³
<u>Given:</u>
r = 7
<u>Work:</u>
V = 4/3πr³
V = 4/3π(7³)
V = 4/3π(343)
V = 1436.76
Cost of month plan = $40
Cost of minutes used = $0.45 after 700 minutes
Total cost = $48.10
Let x be the total minutes used
Total cost = 40 + 0.45(x - 700)
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Form the equation and solve x
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40 + 0.45(x - 700) = 48.10
40 + 0.45x - 315 = 48.10
0.45x - 275 = 48.10
0.45x = 48.10 + 275
0.45x = 323.10
x = 323.10 ÷ 0.45
x = 718
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Answer: John had used 718 mins this month
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He should change the coefficient 5
Where's the net. We need the net to answer the question
The correct option is: B. 
<u><em>Explanation</em></u>
<u>The general form of growth equation</u> is:
, where A = final amount, P = initial amount, r = growth rate in decimal form and t = time duration
Here, the speed of the rocket at the beginning was 5,000 kilometers per hour and at the end will be 25,000 kilometers per hour. The speed increases at a rate of 4.3% per minute.
That means, 
Now <u>plugging these values into the above equation</u>, we will get......

So, the equation that could be used to determine the time for the speed of the rocket to reach 25,000 kilometers per hour will be: 