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 :

Among the given choices, the right statement is that computers are advantageous because it holds a larger amount of data over graphing calculators. Calculators are easier to transport and has lower power consumption. Answer here is D.
Protons and neutrons are in the nucleus of an atom, whereas electrons are present in orbitals, or shells, outside an atom. Electrons are negatively charged, protons positive, and neutrons have no charge, or are neutral. Protons and neutrons have a relative mass of approx. 1 Atomic Mass Unit (amu), whereas electrons have a relative mass of approx 0.00055 amu.
Answer is: d. increases.
<span>The velocity of sound in seawater changes with water pressure, depth, temperature and salinity.
</span>Velocity can be calculeted using Del Grosso's equation, the UNESCO equation (<span>International Standard algorithm)</span> or <span>Mackenzie equation.
To measure velocity navy use </span>Expendable Bathy Thermograph.