I need a essay on what I learned in chemistry

Which change to the system wood cause the freely-moving piston to lower?

The activation energy for the reaction no2(g)+co2(g)⟶no(g)+co(g) is ea = 300 kj/mol and the change in enthalpy for the reaction is δh = -100 kj/mol . what is the activation energy for the reverse reaction?

My plate recommends that of your nutritional intake comes from fruits and vegetables. a. 30% b. 50% c. 20% d. 40%