Answer: With atomic number 20, calcium atoms have 20 positive protons, and the ion has only 18 electrons, which means the net charge is +2. Calcium ions are essential for muscle contractions, nerve impulses, and bone maintenance.
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Answer:
D
Explanation:I alredy know this i am in 7th gread
Answer:
b)5l x 10kg c)10kg + 9l (Not sure for the last 1)
