In addition to the six elements most prevalent in living things there are other elements that are required for human life. which element is necessary for humans to maintain a strong skeletal system?
a. xenon
b. calcium
c. rhodium
d. chlorine

What is the ph of a solution with a 1.50 × 10−9 m hydroxide ion concentration?

Which describes interactions between substances and stomata during photosynthesis? check all that apply. oxygen enters stomata. oxygen is released through stomata. carbon dioxide enters stomata. carbon dioxide is released through stomata. hydrogen enters stomata. hydrogen is released through stomata.

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