* Mechanical Kinetic Energy: This is the energy an object possesses due to its motion. The formula for kinetic energy is: KE = (1/2) * mass * velocity²

* Spring Compressed Rock: While the rock has potential energy stored in the spring, it's not moving. Therefore, it has zero kinetic energy.

* Bicycle Going 10 mph: Has kinetic energy because it's moving.

* Car Going 60 mph: Has kinetic energy because it's moving, and it's much heavier than the bicycle and moving faster.

Conclusion: The car going 60 mph will have the most mechanical kinetic energy because it has the highest mass and highest velocity.