Answer:
7536 
Step-by-step explanation:
Given that:
Rate of decreasing of radius = 12 km/sec
Height of cylinder is fixed at = 2.5 km
Radius of cylinder = 40 km
To find:
The rate of change of Volume of the cylinder?
Solution:
First of all, let us have a look at the formula for volume of a cylinder.

Where
is the radius and
is the height of cylinder.
As per question statement:
= 40 km (variable)
= 2.5 (constant)

As
are constant:

Answer:
Step-by-step explained
Sleep,eat well,drink plenty of water.Attened any revision plans.
D. (xy2 + 3z14)(x2y4 – 3xy2z14 + 9z28
Answer:
69.08
Step-by-step explanation:
π×d
3.14×22=69.08
(3x + 1/2 ) + ( 7x - 4 1/2 )
3x+7x + 1/2 - 4 1/2
10x -4