Answer:
speciation is when one species splits off into multiple species.
In-depth answer:
Speciation can happen in 4 different ways, the first being Allopatric Speciation, where 2 groups of the same species are physically separated for extended periods of time, and when they're re-introduced, they don't breed.
Sympatric Speciation is when 2 groups of the same species aren't seperated, but form different behaviors that isolate them reproductively (the groups wont inter-breed)
Parapatric Speciation is when 2 groups of the same species are suddenly placed into a new environmental niche, and adapt in different ways to fill that niche.
Quantum Speciation is much less recognized, but it's when a new species rapidly evolves and 'buds off' from the original group
1. Answer: to answer questions about the natural world
The aim of scientific method is to answer a question that the scientist have. To answer the question, the scientist need to design a research or observation. If the research is flawed, the result might not match with the scientist aim and the conclusion will be wrong. Scientific method can be used to help design the research so it will have less flaw
2. Answer: fertilizer
The student wants to determine the effect of a certain brand of liquid fertilizer on the growth of ivy. The fertilizer are hoped to influence the growth of the ivy. Independent variable is the variable that hoped to influence the dependent variable. So, the independent variable would be fertilizer and the dependent variable would be the growth.