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:What should you do if you realize during research that your original theory is wrong
Explanation:
Answer:
the mesopelagic, dysphotic, or twilight zone
Explanation:
Marine zones are the divisions of the ocean. The ocean is divided into two basic parts; the pelagic or open ocean, and the benthic or sea floor.
The pelagic zone is further divided into five broad zones according to how far down sunlight penetrates and they are:
1) the epipelagic, euphotic, or sunlit zone: the top layer of the ocean where enough sunlight penetrates for plants to carry on photosynthesis.
2) the mesopelagic, dysphotic, or twilight zone: a dim zone where some light penetrates, but not enough for plants to grow.
3) the bathypelagic, aphotic, or midnight zone: the deep ocean layer where no light penetrates.
4) the abyssal zone: the pitch-black bottom layer of the ocean; the water here is almost freezing and its pressure is immense.
5) the hadal zone: the waters found in the ocean's deepest trenches.
I believe d is the correct answer
major conflict. Ellen continually suffers abuse by her neglectful caretakers and searches for a stable home and loving family. rising action. Ellen is placed in a number of temporary homes, all of which are unhappy, and she longs for a home where she is loved and cared for.