Pigments in photosystem 1 use energy from light to reenergize the electrons.
c. because only male repoduce sperm
Answer:
precipitation is the answer of this question
One reason is for safety! in case you get stranded in a body of water you can keep yourself afloat
Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray Group 2 alkaline earth metal, fifth-most-abundant element by mass in the Earth's crust. The ion Ca2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.[5] Free calcium metal is too reactive to occur in nature. Calcium is produced in supernova nucleosynthesis.