(3) 3.82 days and alpha decay is your answer.
The answer is option A.
That is A: They have shown how lead can build up and cause damage in the human body.
Lead had been used in plumbing and other products since ancient times. chemists showed that how lead can build up and cause damage in the human body.
Chemists have discovered lead toxicity and showed that it can cause damage in the human body since it is a toxic element.
When a strong acid and strong base are combined, it forms a neutral salt. Therefore, Na₂SO₄ is a neutral salt because it is the product of NaOH (a strong base) and H₂SO₄ (a strong acid).
Neutral, because anything too acidic or basic would kill a person
I believe the correct answer is A) 6