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 :

Answer:
in the air and soil
in drinking water
on and inside the human body
Explanation: Hope that helps
Answer:
the equator is closer to the sun
Hello!
Find the Energy of the Photon by Planck's Equation, given:
E (photon energy) =? (in Joule)
h (Planck's constant) = 
f (radiation frequency) =
Therefore, we have:





I Hope this helps, greetings ... DexteR! =)