I need help in chemistry

Which is true of transition metals when moving from left to right on the periodic table? the d sublevels are not filled across the period. the cation radii become larger across the period. atomic radii increase slightly and then start to decrease. atomic radii decrease slightly and then start to increase. o

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. which postulate of kinetic molecular theory best explains how this is possible?

What must happen before a body cell can begin mitotic cell division