What do elements in the first two columns of the periodic table have in common?

How many moles of magnesium is 3.01 x10^22 atoms of magnesium?

The blackbody curve for a star name zeta is shown below. what is the peak wavelength for this star ?

One way that radioactive waste is treated is by burying it in repositories. the repositories are found only in states with very low populations. true or false? a. trueb. false(also i meant to put high school but it put down middle school instead)