Soil type would be a factor that does not influence mass movement
1) B
(I'm not so sure of this one) All of the other options have a steady impact on population regardless of the density of organisms except competition
2) D
Increased carbon dioxide levels would not hinder plant growth, and tsunamis aren't really linked to carbon dioxide levels. Increased carbon dioxide is unlikely to lower the air temperature so only D is left.
3) A
4) Three properties of water that allow it to sustain life are that it is adhesive, it is a good solvent, and cohesion. Adhesion is important in situations such as water travelling up xylem tubes in plants so that the water is not pulled down by gravity and can reach parts of the plant that need water. Cohesion allows the water being pulled up the xylem to stay together and for water molecules to be pulled when a neighbouring one is moved. Water being a good solvent allows inorganic minerals to be taken with water through vascular tissue, such as in the previous example.
Climate, Land form/shape and fossils(he was most interested in this)
Answer:
The t-test
Explanation:
<em>The researcher should use a t-test to compare the two means and check if they are significantly different from each other.</em>
In using the t-test, both null (H0) and alternate (H1) hypothesis are made such that:
Thereafter, the value of t is calculated and compared to its critical value on the table. The formula for calculating the t goes thus:
where, Y1 = mean of population 1, Y2 = mean of population 2, S1 = variance of population 1, S2 = variance of population 2, n1 = number of individuals in population 1 and s2 = number of individuals in population 2.
<em>At the end of the day, if the calculated t value is more than the critical value of t, the H0 is rejected and it shows that the two means are significantly different. Otherwise, the H0 is accepted and this shows that there is not significant difference between the mean of population 1 and that of 2.</em>