Answer:
ai) 73000 gal/yr
aii) $730 per year
b) 1000 days
Step-by-step explanation:
ai) The water usage per day is ...
(4 showers/day)(10 min/shower)(5 gal/min) = 200 gal/day
Then the usage per year is ...
(200 gal/day)(365 days/yr) = 73,000 gal/yr
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aii) The cost of electricity is the cost of heating half the water usage, so is ...
(0.20 kWh/gal)(1/2)(73,000 gal/yr)($0.10/kWh) = $730/yr
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b) The current daily cost of electricity for heating water is ...
($730/yr)/(365 days/yr) = $2/day
If the cost is cut in half, it will be $1 per day. That means the savings is $1 per day, so it will take 1000 days to recover the $1000 initial cost. (Effectively, the average cost for the first 1000 days is the same as if the water heater had not been replaced.)
The volume of a gas in a container varies inversely with the pressure on the gas. If a gas has a volume of <span>250 </span>cubic inches under a pressure of<span>
</span><span>4 </span>pounds per square inch, what will be its volume if the pressure is increased to 20 pounds per square inch? (Round off your answer to the nearest cubic inch.)
Answer:
18
Step-by-step explanation:
The multiples of 9 are 9,18,27,36,45,54,63,...
The multiples of 6 are 6,12,18,24,30,36,42,...