Answer: 
Step-by-step explanation:
The missing figure is attached.
The perimeter of a rectangle is:
Where "l" is the lenght and "w" is the width.
You can identify in the figure that:
Then, knowing the perimeter of the rectangle, you can make the subsitution into the formula:
Now you must simplify and solve for "z"
Finally, substituting the value of "z" into 
, you get:
We know that
[surface area of a sphere]=4*pi*r²
r²=surface area/(4*pi)
r=√[surface area/(4*pi)]
surface area=450 in²
r=√[450/(4*pi)]------> r=5.98 in------------> r=6 in
the answer is
r=6 in
Answer: 22 Levels
Step-by-step explanation: He would need to go one level higher just to get to level one, and another 21 to get to the level that he wants to, so the total would be 22 levels.
