Answer:
DE = 1.2ft
Step-by-step explanation:
It's actually a lot easier for someone to just draw a diagram. I recommend it in the future!
This is a right-angle triangle, so I'm guessing it's Sohcahtoa.
cos23° = DE/1.3
DE = 1.3cos 23°
DE = 1.1966...
Rounded:
DE = 1.2
Answer:
The rate of change of the area of the circle is approximately
.
Step-by-step explanation:
Given:

radius 
We need to find the rate of change of the area of the circle at that instant.
Solution:
Now we know that;
Area of the circle is given by π times square of the radius.
framing in equation form we get;

to find the rate of change of the area of the circle at that instant we need to take the derivative on both side.

Substituting the given values we get;

Hence The rate of change of the area of the circle is approximately
.