Answer: Chemical
Explanation: because it is changeing its chemical structure if its wrong sorry .
I would think that you would have to do 42/2=21Hz, but I'm not sure...
Answer:
Newton's second law of motion states that the acceleration of a system is directly proportional to and in the same direction as the net external force acting on the system, and inversely proportional to its mass. In equation form, Newton's second law of motion is a=Fnetm a = F net m .
Explanation: