For a constant-velocity object, the average and instantaneous are the same. So the answer is no. It's like taking a running average of a string of numbers that are all the same number. The average is always the sum of the numbers divided by how many have accumulated, which will always equate to the repeated number.
A person's weight will change if they move from the earth to the moon. This does not however, change the person's mass. Mass is the amount of matter that makes up an object, and volume is how much space it takes up. On the moon, there is a lighter gravitational pull on said person, so they will not weigh as much if they stepped on a scale.
Acceleration formulae is:
a=Fnet/mass
According to the question
a=7500N/1500kg
a=5m/s sq.
I would say that insofar as the two stars temperatures are presumably closely related to their luminosity, that the blue star at 156,100 k compared to 3000k for the red star then the blue star has a luminosity of 52 times that of the red star.