C. Lenses form images byvrefracting light; mirrors do not
Answer:
#See solution for details.
Explanation:
-An electromagnet's field can be rapidly changed by just controlling the amount of current. The magnetic strength can be varied over time.
-This way, only a sufficient amount of current will be supplied to meet the needs.
-Unlike the electromagnet, the permanent magnet has a fixed magnetic strength and can only lift a specified weight.
The correct answer is<span> B.The speed of sound in air is directly proportional to the temperature of the air.
When the temperature increases so does the speed of sound. Sound is faster by </span>0.60 m/s for every higher degree in air temperature because the air density is reduced and the sound can travel faster.
The answer that I got was 5'8333..., which is the total for height and in inches, all of this would be 70 inches, or 1.78 meters, or 178 centimeters, or 1780 millimeters, but just go for the height that person is going to be at, 5'833... (this is repeated so just round it up to 5'8 if you want to.)
Hope this helped!
Nate
