Help me please, i’m really confused.

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

explanation:

a