What is the change in the kinetic energy of the bullet-block system as a result of the collision assuming the block is free to move

There is no graph to look at on here, but i shall explain them to you. a line graph is just in its title it’s a graph with a line running through the dots to show an increase or decrease. a bar graph is used to show how much or how little something is so a comparison. a scatter plot is used to graph points to tell the data. and i don’t know what a histogram is.

The answer is 12, for the points