At which point is the air at its highest density?

The difference between the air pressure causes the air to become denser and this also leads to the formation of clouds.  

Hence the option B is correct.

Learn more about the air at its highest density.

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when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27