Answer:
No
Explanation:
The Earth would not have seasons if there is no revolution because the temperatures would not change.
Answer:
Kinetic energy: 
Velocity: 
Explanation:
From the equations of the photo-electric effect,
We know:
Where,
1.
is the Planck's constant which is 
2.
are the frequency of light emitted and threshold frequencies respectively.
3.
is the kinetic energy of the electrons emitted.
By fact, we come to know that the threshold frequency of Zn is 300nm
And also 
Where ,
1. 
is the speed of light 
2.
is the wavelength.
Thus,
Now to find velocity:
The combination of the of two or more elements is known as a compound.
A homogenous mixture has a uniform composition all throughout. They are
similar in terms of the amount of composition present in a solution. For
example, oxygen is diatomic, O2. So oxygen is a compound because it has 2
elements combined in it. It is also a homogenous mixture if there are a lot of
O2 gases present in let’s say tank. They only differ in the place where they
are present. A compound is a representation of one molecule whereas a
homogenous mixture is present in a a solution.
