1) 8 41/48
2) 9 16/27
3) 41 2/5
4) 13 55/63
hope this helps x
For the answer to the question above, I'll show my solution for the answer below.
Area A = pi r^2
<span>The rate of change of area = d A/ d t = 2 pi r d r/d t </span>
<span>r= 2t, d r = 2 d t </span>
<span>This gives </span>
<span>d A/ d t = 2 pi 2t 2 d t = 8 pi t dt </span>
<span>Integrate it </span>
<span>A= 4 pi t^2. </span>
<span>After t=5, the area will be 100* 3.14 square= 314 square units.</span>
From the given question we come to know of certain number of facts and they are:
At 1:00 PM the water level of the pond was = 13 inches
At 1:30 PM the water level of the pond was = 18 inches
At 2:30 PM the water level of the pond was = 28 inches
From the above given facts we can easily find the amount of water changing every half an hour.
Amount of increase in water from 1:00PM to 1:30 PM = (18 - 13) inches
= 5 inches
Amount of increase in water level from 1:30PM to 2:30PM = (28 -18) inches
= 10 inches
From the above two deductions we can come to the conclusion the the constant rate of change in water level is 5 inches for every half an hour.
or
<-- there's no plus/minus sign.
<-- root.
<-- root.
<-- don't forget to distribute the negative.