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
Answer:
17.72° or 72.28°
Explanation:
u = 6.5 m/s
R = 2.5 m
Let the angle of projection is θ.
Use the formula for the horizontal range


Sin 2θ = 0.58
2θ = 35.5°
θ = 17.72°
As we know that the range is same for the two angles which are complementary to each other.
So, the other angle is 90° - 17.72° = 72.28°
Thus, the two angles of projection are 17.72° or 72.28°.
I can help you with that if you translate to English
Answer: Brightness consistency
There are three types of perceptual consistency
Types of Perceptual Constancy: Shape, Size, and Brightness Size constancy
Since the moon and sun affect light, brightness consistency is occurring.
Brightness constancy is our visual ability to perceive objects as having the same level of brightness even though the level of lighting changes.