The correct answer is B. Measurable
Explanation:
The use of science to investigate a phenomenon implies using measurements and observations to better understand a phenomenon or test a hypothesis. Moreover, science focuses on natural phenomena that can be objectively studied through measurement instruments such as a thermometer, balance, hydrometer, etc.
In this context, for a phenomenon to be studied by science this needs to be measurable because the use of precise instruments as wells as numbers allow scientist to analyze and understand a phenomenon. Moreover, phenomena that depend on personal perspectives and cannot be measure is considered as non-scientific.
Answer:
162.78 m/s is the most probable speed of a helium atom.
Explanation:
The most probable speed:

= Boltzmann’s constant =
T = temperature of the gas
m = mass of the gas particle.
Given, m = 
T = 6.4 K
Substituting all the given values :


162.78 m/s is the most probable speed of a helium atom.
Explanation:
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