The radius of a right circular cone is increasing at a rate of 1.4 in/s while its height is decreasing at a rate of 2.8 in/s. At what rate is the volume of the cone changing when the radius is 138 in. and the height is 143 in.?

34191.7πin³/sec

Step-by-step explanation:

Volume of circular come = 1/3pi x r² x h

When we differentiate this formula we have

dv/dt = 1/3π[r²dh/dt + 2rhdr/dt]

We have the following information

r = 138

H = 143 inch

dr/dt = 1.4

dh/dt = -2.8

When we plug into the formula

1/3π[130² x -2.8 + 2x138x143x1.4]

= 34191.7πin³/sec

l.ln.lln.k.nkl

step-by-step explanation:

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.