Question

at a given temperature, what is true of all gas molecules?
they have the same mass
they have the same type of bonding.
they have the same speed.
they have the same average kinetic energy.

Explanation:

The average kinetic energy of gas molecules is directly proportional to the temperature. At a given temperature, all gas molecules, regardless of their mass, type of bonding or speed, have the same average kinetic energy. Different gases can have different masses and types of bonding. Also, gas - molecules have a distribution of speeds (Maxwell - Boltzmann distribution) at a given temperature.

Answer:

They have the same average kinetic energy.