129 degrees you just add DCE and ECF together
<span>Semicircle area = circle area / 2 = (pi*r^2)/2
16 in is the radius. Let's call the area of this semicircle s.
3.14*16^2=s
</span><span>Trapezoid area = ((base 1 + base 2) / 2) * h
Here, base 1 is 44 and base 2 is 36. The height (h) is 20. Let's call this trapezoid's area t.
(44+36)/2 *20 = t
</span>
<span>We can remove the area of the semicircle (that created by the windshield wiper) by subtracting it from the area of the trapezoid.
t - s = uncleaned area
[(44+36)/2 * 20] - [3.14 * 16^2] = uncleaned area</span>
Step-by-step explanation:
remember. the radius is always half the diameter.
volume of a cylinder
pi × r² × height
pi×7.5²×48 = pi×56.25×48 = 8,482.300165... in³
volume of a sphere
4/3 × pi × r³
and that volume should be the same as the cylinder. so,
4/3 × pi × r³ = pi×56.25×48
4/3 × r³ = 56.25 × 48
1/3 × r³ = 56.25 × 12
r³ = 56.25 × 36 = 7.5² × 6² = (7.5×6)² = 45² = 2025
which would be 12.65148998... in.