Answer: The volume of shell is 12.8π mm².
Step-by-step explanation:
Since we have given that
Radius to the inside of the shell = 4 milimeters
Radius to the outside of the shell = 4.2 milimeters
Since r changes from 4 mm to 4.2 mm
so, 
As we know that
Volume of shell is given by


So, the volume of shell is 12.8π mm².
Answer:
x = 80 degrees
Step-by-step explanation:
Answer:
<em>It will take 12 hours to fill the tank</em>
Step-by-step explanation:
Proportions
Tap A fills a tank in 4 hours. It means each hour it fills 1/4 of the tank.
Tap B fills the tank in 3 hours. Each hour it fills 1/3 of the tank.
Tap C empties the tank when full in 2 hours. Each hour it empties 1/2 of the tank.
Each hour, the tank gets filled by:

Since the tank fills 1/12 of its capacity in one hour, it follows that it will take 12 hours to fill the tank
-0.5
Answer: -0.5
Step-by-step explanation: