Answer:
D
Explanation:
This is because the atmosphere is refreshable and makes breathing so conducive.
The organelle that temporarily breaks apart so that the DNA can divide up is the nucleus. Nucleus store most of the cell's DNA it is responsible for carrying genetic information. It is also responsible for generating genetic expression to ensure the proper activities of the entire cells.
Answer:

Explanation:
The distance to the Sun is 5,890,000,000,000. We need to write this distance in km.
A number can be written as
in scientific notation where x is a real no and y is any integer.
There are 10 zeros in the given number and also there are 12 digits after. It would mean that,

So, the distance in scientific notation is : 
Children begin to form a self concept around 18 months of age
The leafs would contain more Chloroplasts, that is where photosynthesis occurs!