I think the answer you're looking for is -are randomly oriented. if not sorry... i tried.
Answer:
1. Least massive stars are the coolest and least luminous, lower right of main sequence, on HR diagram.
2. Most massive are the hottest and most luminous, upper left of main sequence on Hr Diagram.
3. The radius of stars are related to their sprectral type. having the O being the hottest upper left and M being the coolest bottom right.
Let say the two train cars are of masses
and 
now if the speed of two cars are
and 
then we can say that the momentum of two cars before they collide is given by

here two cars are moving in opposite direction so we can say that the net momentum is subtraction of two cars momentum.
Now since in these two car motion there is no external force on them while they collide
So the momentum of two cars are always conserved.
hence we can say that the final momentum of two cars will be same after collision as it is before collision

Well the basic equation for velocity is v=d/t where d is distance and t is time. So v=2m/50s and the answer is v=0.04meter/second.
Answer:
Explanation:
velocity of projection, vo = 381 m/s
angle of projection, θ = 73.5°
The formula for the range is


R = 8067.4 m
Range in shorten by 34.1 %
So, the new range is
R' = 8067.4 - 34.1 x 8067.4/100
R' = 5316.4 m