The number of hours required : 37.2 hours
<h3>Further explanation</h3>
Given
⁴²K (potassium -42)
Required
The number of hours
Solution
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours
For three half-life periods :

It has two elements.
Magnesium shows +2and Cl shows -1.
When you pass around the side dishes at this year's Thanksgiving feast, here's one thing to be thankful for: you're eating mashed potatoes instead of mashed paper towels. But if you were chewing on the towels instead of the spuds, would you even know it.
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Answer:
A. SR
Explanation:
SR is strongtium and is an electronegative element:))
hope this helps:))