Answer:
x) there is less demand at night
Explanation:
Electric power and it's the price is dependant on the level of demand it has, there are peak and off-peak times during the day, generally speaking <em>during the night (between 10 pm and 7 am) electricity has lower demand</em>.
The existence of peak times at a day is the reason why<em> hydroelectric generation is lower at night</em>, normally in peak off times the hydroelectric generator stores water for when the demand increases, same happens with <em>powerplants at night not being as efficient as they are during the day when the energy is more needed.</em> Finally, <em>pollution control is stringent at all times of the day, its not related to the demand.</em>
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