Answer:B,C,D
Explanation:
Thermodynamic efficiency is given by
efficiency can be increased by Keeping 
constant and increasing 
Keeping constant and decreasing 
by increasing 
by decreasing 
ratio
M= Height of image/height of the object
If, M>1, then height of image>height of object.
And therefore, image is larger than the object.
Answer:
1)SI is coherent system of units
2) SI is rational system of units
Answer:
35.14°C
Explanation:
The equation for linear thermal expansion is 
, which means that a bar of length 
with a thermal expansion coefficient 
under a temperature variation 
will experiment a length variation 
.
We have then = 0.481 foot, = 1671 feet and = 0.000013 per centigrade degree (this is just the linear thermal expansion of steel that you must find in a table), which means from the equation for linear thermal expansion that we have a 
= 22.14°. As said before, these degrees are centigrades (Celsius or Kelvin, it does not matter since it is only a variation), and the foot units cancel on the equation, showing no further conversion was needed.
Since our temperature on a cool spring day was 13.0°C, our new temperature must be 
= 35.14°C
D) waves are used to transmit the rail signal though the air. these waves are encoded at different frequencies for different stations
