Answer:
a)
, b) 
Explanation:
a) According to the First Law of Thermodinamics, the system is not reporting any work, mass or heat interactions. Besides, let consider that such box is rigid and, therefore, heat contained inside is the consequence of internal energy.

The internal energy for a monoatomic ideal gas is:

Let assume that cubical box contains just one kilomole of monoatomic gas. Then, the temperature is determined from the Equation of State for Ideal Gases:



The thermal energy contained by the gas is:


b) The physical model for the cat is constructed from Work-Energy Theorem:

The speed of the cat is obtained by isolating the respective variable and the replacement of every known variable by numerical values:



<span>A body wave is a seismic wave that moves through the interior of the earth, as opposed to surface waves that travel near the earth's surface.
P and S waves are body waves. Each type of wave shakes the ground in different ways</span>
When the heat of the sun shines on the water<span> in oceans, lakes, rivers and streams, the </span>water<span> evaporates, rising up into the air as </span>water<span> vapor. As it moves higher into the sky, it cools.
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<span>You could easily define it this way. This would be valid. But for most of history it was unclear when a baby was conceived, so it would be silly for someone to say their baby was 9 months old when it was actually born at only 8.5 months. Days of conception similarly would not be a good substitute for birthdays because no one would know them. Then in general it was much easier to mark someone's age as when they came into the world as an independent being, and this tradition is far too entrenched (and simple and easy to handle and universal for people in poor countries etc) to think we would at all gain from now finding exactly the date of conception and counting age from that point.</span>
I think it’s the Full Moon