There are some missing data in the text of the problem. I've found them online:
a) coefficient of friction dry steel piston - steel cilinder: 0.3
b) coefficient of friction with oil in between the surfaces: 0.03
Solution:
a) The force F applied by the person (300 N) must be at least equal to the frictional force, given by:

where

is the coefficient of friction, while N is the normal force. So we have:

since we know that F=300 N and

, we can find N, the magnitude of the normal force:

b) The problem is identical to that of the first part; however, this time the coefficienct of friction is

due to the presence of the oil. Therefore, we have:
Answer:
26945.6 ft⋅lbf
Explanation:
Volume of Right Circular Cone = pi*(radius^2)*(height/3)
Pi*(4)*(5/3) = 20.94 ft^3
Density = Mass / Volume
Mass = Density*Volume
Mass = (40)*(20.94)
Mass = 837.6 lb
Work = Force*Height
Force = Mass*Acceleration
Acceleration will be gravitational acceleration
Work = (837.6)*(32.17)*(1)
Work = 26945.6 ft⋅lbf
The cluster that is most likely to be located in the halo of our galaxy is the diagram that shows main-sequence stars of every spectral type except O, along with a few giants and supergiants.
<h3>What are star clusters?</h3>
Star clusters are large collections of stars. Star clusters are classified into two types: Globular clusters are gravitationally bound groups of tens of thousands to millions of old stars.
Because of their location on the dusty spiral arms of spiral galaxies, they are sometimes referred to as galactic clusters. Stars in an open cluster share a common ancestor as they all formed from the same massive molecular cloud.
A typical spiral galaxy has a faint, extended stellar halo. A stellar halo is an essentially spherical population of stars and globular clusters thought to surround most disk galaxies and the cD class of elliptical galaxies. It should be noted that a halo is a spherical cloud of stars surrounding a galaxy. Astronomers have proposed that the Milky Way's halo is composed of two populations of stars.
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