The dimensions of the bottom of the drawer are:
20 cm × 40 cm
So the area is : 800 cm² (rectangular shaped)
The area formula of a circle is:

r²
The diameter of the plate is 20cm
so the radius is half the diameter which is 10cm
Apply the given to the formula:

(10)²
100

314.16 cm²
2 plates in the bottom drawer
Area of two plates:
2 × 314.16
628.32 cm²
Area of the non-covered space in the bottom drawer:
Area of drawer - area of two plates
800 - 628.32
171.68 cm²
The external angle between the secants (20°) is half the difference of the intercepted arcs.
(75° - B)/2 = 20°
75° - B = 40°
75° - 40° = B = 35°
A = 2bs + b^2; where A = area of pyramid; b = base length; s = the slant height;
136 = 8s + 16 ;
8s = 120;
s = 15 inches;
It’s 20000 but not sure about it
No it does NOT make sense to state density in kilograms per square meter. Density has to be stated in terms of mass per unit of volume and NOT per unit of area.