Hey there! I'm happy to help!
First, let's find the radius. The radius is half of the diameter.
8.4/2=4.2
Here's how to find the area of a circle.
Square the radius.
4.2²=17.64
And multiply by pi (3.14 in our case)
17.64(3.14)=55.3896
We round to the nearest tenth, giving us an area of 55.4 ft²
Have a wonderful day! :D
C
Angle 1 and 2 make up a straight angles and straight angles always equal 180.
Subtract 35 from 180 to find Angle 2s measure which is 145
If two lines are perpendicular then they have slopes that are negative reciporacols of eachother.
If

then