Answer:
The correct option is: stable environment
Explanation:
According to the Darwin's theory, natural selection is the concept by which all the small useful variations of traits are preserved.
According to Darwin, there are three <u>necessary and sufficient conditions</u> for the occurrence of natural selection:
1. struggle for existence
2. variation
3. inheritance
These conditions are said to be necessary because if these conditions are not satisfied then natural selection does not occur.
These conditions are said to be sufficient because if these conditions are satisfied, then natural selection will most definitely occur.
Answer:
The forces acting on the book are balanced by each other.
Answer:
156 Hydrogen atoms
Explanation:
<u>Any acyclic alkane has a molecular formula that can be expressed as</u>:
CₙH₂ₙ₊₂
Where <em>n</em> is any integer and the number of carbon atoms. For example, Propane has 3 carbon atoms, this means it would have [2*3+2] 8 hydrogen atoms, resulting with a formula of C₃H₈.
An acyclic alkane with 77 carbon atoms would thus have:
2*77 + 2 = 156 hydrogen atoms
Double replacement i believe
