Answer:
The answer in the procedure
Step-by-step explanation:
we know that
The lateral area of a cone is equal to

where
r is the radius of the base
l is the slant height
we have


assume 
substitute the values

This value is an underestimate, because the assumed pi value is less than the real value
assumed value 
real value 
Interior alternate angles
Answer:
I think the answer is d.)120
Answer:
W = 21.44*10⁶J
Step-by-step explanation:
Given
y = x² (0 < x < 4)
γ = 10000 N/m³
W = ?
If we apply
y = 4² = 16 = h
y = x² ⇒ x = √y
then
V = π*(√y)²*dy = π*y*dy
W = (γ*V) *(16-y) = γ*π*y*dy*(16-y)
⇒ W = γ*π*∫y*(16-y)dy = γ*π*(8y²-(y³/3))
finally we obtain (0 < y < 16)
W = γ*π*(8y²-(y³/3)) = 10000*π*(8*16²-(16³/3)) = 21.44*10⁶J