Answer:
Volume of the cone = 
Step-by-step explanation:
Volume of a right circular cone:

For, h=3.9 feet
r= 14.7 feet
As, 
Volume :

Volume of the cone is 
The straight line is given by the equation
y=kx+b
We substitute coordinates of points
-21=-66k+b (1)
2=-67k+b (2)
We give a system of equations
Solution of this system:
(1) b=66k-21
(2) 20=-67k+66k-21
20=-k-21
k=-21-20
k=-41
b=-41*66-21=-2727
y=-41x-2727
Answer:
downtown workers
Step-by-step explanation:
The research group should do the survey with downtown workers in order to find the opinions for the construction of a new downtown parking garage in downtown. Since the workers need to commute to downtown for work by various modes such as buses, private vehicles, bicycles, taxis, share vehicles, etc., therefore the the research group will get maximum useful information from the downtown workers for the construction of a new parking garage.
Thus, option "downtown workers" is correct.
Ok, so you already know that mQBO = 3x-15°
You just need to find x.
You use mSAO and mQAO to solve for x. You can also see that triangle AOS and triangle AQO are similar. Solve these two equations for x and mAOQ:
90+(2x+6)+mAOQ = 180
90+(4x-12)+mAOS = 180
x=9 and mAOQ=mAOS=66°
Now you can find mQBO, by simple algebra:
3x-15=3*9-15=12
So, mQBO is12 degrees.