Oil spill on land and in the oceans and kills wildlife like the great barear reef
Answer:
0.544 eV
Explanation:
To ionize the hydrogen atom 
So the required energy is
as
So 
We have to calculate the energy required to ionize hydrogen atom when it is in n=5
So the energy should be less than 
Answer:
4776.98 N is the minimum force to start the rise.
Explanation:
We can use the first Newton's law to find the minimum force to move the block.
So we will have:

Where:
- F is the force
- W(x) is the weight of the block in the x direction, W = mg*sin(15)
- F(f) is the static friction force (F(f) = μN), μ is the static friction coefficient 0.4.





Therefore 4776.98 N is the minimum force to move the block.
I hope it helps you!
You could use clay, sticks, rocks, Legos,