F=ma 2018 Part B Problem 3

A 3.0 \mathrm{~kg} mass moving at 40 \mathrm{~m} / \mathrm{s} to the right collides with and sticks to a 2.0 \mathrm{~kg} mass traveling at 20 \mathrm{~m} / \mathrm{s} to the right. After the collision, the kinetic energy of the system is closest to

Answer Choices
A. 600 \mathrm{~J}
B. 1200 \mathrm{~J}
C. 2600 \mathrm{~J}
D. 2800 \mathrm{~J}
E. 3400 \mathrm{~J}