Options for the question have not been given. They are as follows:
type of soil
type of plants
exposure to sunlight
method for measuring the growth
Answer:
exposure to sunlight
Explanation:
A scientific experiment has an experimental group and a control group. Control group is included to omit any error in results due to the factors other than the variable factor. Experimental group is the one exposed to different levels of the variable factor.
Here, Carlo wants to determine the the effect of day length on plants' growth. The test variable here is thus the duration of sunlight. In experimental group, this duration will be changed to determine its effect. In control group it will be kept constant so that results from other factors can be excluded from the observed experimental result.
Answer: The flow of individuals in and out of a population introduces new alleles and increases genetic variation within that population. Mutations are changes to an organism’s DNA that create diversity within a population by introducing new alleles.
Explanation:
Elements in the first row (hydrogen and helium) will have outer electrons in the first energy level. Their principal quantum number is 1. Elements in the second row (lithium through neon) will have valence electrons in the second energy level with a principal quantum number of 2.
As of right now, the land is pretty spread out. But millions of years ago, like, we're talking dino time, all the land was just one chunk. This chunk was called Pangaea, or Pangea. But before everything split apart into multiple continents, there was just one; a supercontinent. Hope that helps!