Answer:
The height of the pile is increasing at the rate of 
Step-by-step explanation:
Given that :
Gravel is being dumped from a conveyor belt at a rate of 20 ft³ /min
i.e 
we know that radius r is always twice the diameter d
i.e d = 2r
Given that :
the shape of a cone whose base diameter and height are always equal.
then d = h = 2r
h = 2r
r = h/2
The volume of a cone can be given by the formula:
Taking the differentiation of volume V with respect to time t; we have:
we know that:
So;we have:
The height of the pile is increasing at the rate of
Answer:
Step-by-step explanation:
In order to add or subtract numbers in scientific notation, the powers of ten must have the same exponent. In this caes the diameter of an average human body cell is a power of -4 and the diameter of a plant cell is a power of -3. In order to add them, we can move the decimal over for the body cell diameter:
Add the two values: 
I believe the correct option is C.
Answer:
the second one because 3 divided by 1.5 is 2 then it's right
Answer:
b)(b²-a²)
Step-by-step explanation:
a cotθ + b cosecθ =p
b cotθ + a cosecθ =q
Now,
p²- q²
=(a cotθ + b cosecθ)² - (b cotθ + a cosecθ)² [a²-b²=(a+b)(a-b)]
=(acotθ+bcosecθ + bcotθ+ acosecθ) (a cotθ + bcosecθ -bcotθ-acosecθ)
={a(cotθ+cosecθ)+b(cotθ+cosecθ)} {a (cotθ-cosecθ)+b (cosecθ-cotθ)}
={a(cotθ+cosecθ)+b(cotθ+cosecθ)} [a (cotθ-cosecθ) + {- b (cotθ-cosecθ)} ]
={a(cotθ+cosecθ)+b(cotθ+cosecθ)} {a (cotθ-cosecθ) - b (cotθ-cosecθ)}
={(cotθ+cosecθ)(a+b)} {(cotθ-cosecθ) (a-b)}
=(cotθ+cosecθ) (a+b) (cotθ-cosecθ) (a-b)
=(cotθ+cosecθ) (cotθ-cosecθ) (a+b) (a-b)
= (cot²θ-cosec²θ) (a²-b²) [(a+b) (a-b)= (a²-b²)]
= -1 . (a²-b²) [ 1+cot²θ=cosec²θ ; ∴cot²θ-cosec²θ=-1]
=(b²-a²)
