Number 4 I think
the atomic mass is 11 because the mass is the sum of protons and neutrons
Answer:
<h2>The angular velocity just after collision is given as</h2><h2>

</h2><h2>At the time of collision the hinge point will exert net external force on it so linear momentum is not conserved</h2>
Explanation:
As per given figure we know that there is no external torque about hinge point on the system of given mass
So here we will have

now we can say

so we will have


Linear momentum of the system is not conserved because at the time of collision the hinge point will exert net external force on the system of mass
So we can use angular momentum conservation about the hinge point
It's a multiple of 5 because you can't multiply anything by 2 and get 25
The definition for nebula is : A cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.