To develop the problem, we require the values concerning the conservation of momentum, specifically as given for collisions.
By definition the conservation of momentum tells us that,
To find the speed at which the arrow impacts the apple we turn to the equation of time, in which,

The linear velocity of an object is given by

Replacing the equation of time we have to,

Velocity two is neglected since there is no velocity of said target before the collision, thus,

Clearing for m_2

Answer: The density of glycerine will be 
Explanation:
Density is defined as the mass contained per unit volume.

Given:
Density of glycerine= 
1 lbm = 0.454 kg
1 kg =
Thus 
Also 
Putting in the values we get:

Thus density of glycerine will be 
334kJ ------ 1kg
x. ------- 0,1kg
x = 33,4kJ
is it right?
To solve this problem we will also apply the concept related to the conservation of the mass, which announces that: "In an isolated system, during any ordinary chemical reaction, the total mass in the system remains constant, that is, the mass consumed by the reagents is equal to the mass of the products obtained. "
If the mass is in a closed system, it cannot change. This assessment should not be confused with the transformation of the matter within it, for which it is possible that over time the matter will change from one form to another. For example during a chemical reaction, there is a rupture of links to reorganize into another, but said mass in the closed system is maintained.
The correct answer is:
C. "The mass of a closed system cannot change over time; mass cannot be created or destroyed."