Answer:
5.625¢
Step-by-step explanation:
The amount of energy used by the chandelier is ...
5 × 0.075 kW × 1.5 h = 0.5625 kWh
At 10¢ per kWh, the cost will be ...
0.5625 kWh × 10¢/kWh = 5.625¢ . . . . cost of operation for 90 minutes
The dragons would have to speed up to balance out the time that they slowed down.
The instantaneous rates of changes are all the individual speeds at given times. If you have some that are slow, you will need to have just as many that are fast to balance it out and ensure they have the correct average speed.
Answer:
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