The answer is D, because "Animals without a backbone are invertebrates."
Answer:
Group 2A — The Alkaline Earth Metals. Group 2A (or IIA) of the periodic table are the alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
Explanation:
Cell theory was discovered from the scientist
Weathering and chemical substance weathering
MgCl2
Mg=24
Cl=35.5×2 = 71
rmm= 71+24=95g
1 mole = molar mass
1 mole = 95g
1g = 1/95 moles
345g= 1/95 × 345
3.6 moles