Answer:
a) 1512000 Joules
b) 5040 seconds = 84 minutes = 1.4 hours
Explanation:
Power saved y replacing bulbs = 60-18 = 42 W = 42 J/s
Time the bulb is used for = 10 hours
Energy saved during this time
42×10×60×60 = 1512000 Joules
Saved energy by replacing standard incandescent lightbulbs with energy-efficient compact fluorescent lightbulbs in 10 hours is 1512000 Joules
b) Power the plasma TV uses = 300 W = J/s
\frac{1512000}{300}=5040\ s3001512000=5040 s
Time a plasma TV can be used for with the saved energy is 5040 seconds = 84 minutes = 1.4 hours.
Answer:
<u>d. a row of elements</u>
Explanation:
Elements that are in the same group, have same number of electrons and make up a column in a periodic table.
Answer:
B. Carbon dioxide
Explanation:
A catalytic converter is designed and placed in the exhaust of most automobiles to remove harmful gases from escaping into the environment.
The converter uses palladium and platinum which are both catalyst to reduce harmful gases such as nitrogen oxide which causes acid rain, carbon monoxide which affects human haemoglobin and other hydrocarbons into less harmful ones.
The catalytic converter helps to convert carbon monoxide, a product of incomplete combustion of hydrocarbons into less harmful carbondioxde. Carbon monoxide is a very toxic gas. It causes harm to both plants and animals as well.
Answer:
She should have first notified the teacher.
