1. True.
2. Given: Mass = 30 Kg
Acceleration = 2.0m/s2
Force= mass x acceleration
Force= 30Kg x 2.0 m/s2
Force= 120 N
3. Given : Mass = 30 Kg
Force= 180 N
Force = Mass x Acceleration
Acceleration = Force / Mass
= 180 N / 30 Kg
Acceleration = 6.0 m/s2
When your body turns your food into energy it can heat your body which is called cellular respiration. Not sure if this is what you were looking for?
Their gravitational pull towards the planet?