i. On each of the dots, which represent the blocks while they are in contact during the collision, draw a single arrow to indicate the direction of the net force, if any, exerted on each block. The net force must be represented by a distinct arrow starting on, and pointing away from, the appropriate dot. If the net force is zero for either block, write “zero” under the dot representing that block.

the correct answer is "inertia"

well, their are quite a few differences !

explanation:

first difference is a main sequence star is made of carbon, while a neutron star is made of neutrons. another difference is a main sequence star still has hydrogen to burn, while a neutron star is a remnant of a supernova.

a main sequence star is what’s left over from a low-mass star death, while a neutron star is what’s left from the death of a high-mass star. main sequence star and a neutron star are considered the same thing, except a main sequence star spins.