How is the number of moles of an element determined from a known mass?

Three alkali metals in group 1 are a. calcium, strontium, barium b. boron, aluminum, gallium c. sodium, potassium, rubidium d. fluorine, iodine, chlorine

Select all of the methods through which a drug can enter your body. injection swallowing inhalation absorption

If an area has high air pressure and low humidity, what type of weather will it most likely have? plz !