Answer: Due to his groundbreaking work in math.
1*2*0.2 = 0.4
Pipe drains 0.4m3 in 30min
Volume of tank = 0.5 * (1.4 + 0.6) * 2 * 1 = 2m3
Time taken = 2/0.4 * 30 = 150min
Answer: Choice A. 4 times
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Explanation:
We'll be using this formula

to compute the average rate of change (AROC) from x = a to x = b. Note how this is effectively the slope formula because y = f(x).
To start things off, we'll compute the AROC from x = 1 to x = 2.

Do the same for the AROC from x = 3 to x = 4.

The jump from m = 10 to m = 40 is "times 4", which is why choice A is the final answer.
Based on your other question, I’m going to assume this is 0.37 per $100, not 5,100.
418,700/100 = 4187 (how many groups of $100 the house is worth)
4187 x 0.37 = $1549.19 is her insurance premium