D. all of these can produce nuclear energy
<span>
Evaporation occurred between the reaction of the hydrochloric acid and the arsenic group because there is a formation of gas. A
liquid is cooled if condensation exceeds evaporation. This is because the cooling of the liquid decreases the kinetic energy of the
molecules. Their movement is being restricted by the colder temperature. The
molecules tend to be closer with each other. Also, because of their restricted
movement, the liquid may turn into solid due the colder temperature. An example
of this is the cooling of liquid water by placing it into the refrigerator into
solid water (ice).</span>
Answer: 318 K
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,

where,
= initial pressure of gas = 231 kPa
= final pressure of gas = 168 kPa
= initial volume of gas = 3.25 L
= final volume of gas = 4.35 L
= initial temperature of gas = 
= final temperature of gas = ?
Now put all the given values in the above equation, we get:


At 318 K of temperature will the same gas take up 4.35 liters of space and have a pressure of 168 kPa
Frequency is defined as the number of waves per second. In this machine 25 waves pass in one second.
We need to calculate the number of waves that pass a particular point during one second.
During 2 seconds -25 waves
Therefore in one second - 25/2 = 12.5 waves/s.
1 wave per second has the unit Hertz (Hz)
Therefore answer is 12.5 Hz