Select the correct answer.
What is the perihelion?
A.
It is the point of a planet's orbit that is furthest away from the star it orbits.
B.
It is the distance between the closest natural satellite and the planet it orbits.
C.
It is the distance between an asteroid and the star it orbits.
D.
It is the point of an orbit at which a planet is closest to the star it orbits.

I) a gas contained within a piston-cylinder assembly undergoes two processes, a and b, between the same end states, 1 and 2, where p1 = 10 bar, v1 = 0.1 m3 , u1 = 400 kj and p2 = 1 bar, v2 = 1.0 m3 , u2 = 200 kj: ' process a: process from 1 to 2 during which the pressure-volume relation is pv = constant. ' process b: constant-volume process from state 1 to a pressure of 2 bar, followed by a linear pressure-volume process to state 2. kinetic and potential energy effects can be ignored. for each of the processes a and b, a) sketch the process on a p-v diagram. b) evaluate the work, in kj. c) evaluate the heat transfer, in kj.(ans : qb,12 = -65.0 kj)