Scientists want to determine whether the rapid economic growth in China between 1950 and 2000 caused a mass extinction of animal species during that time period. A mass extinction event is considered to occur when the rate of species extinction for exceeds the background extinction rate. The scientists collected data on the number of extinctions of selected vertebrate species in China between 1950 and 2000, as shown in below Table . Extinction rates were ascertained by measuring the werage percent of species lost(PSL). The average percent of extinctions of 252 protected vertebrate specles in 2,365 countles in China from 1950 to 2000.

Mammals Birds Amphibians and Reptiles Background Rate
Average PSL ± 1 standard deviation 47.4 ± 339 19.75 ± 17.70 28.80 ± 28.86 27.21 ± 16.26

Which of the following is the null hypothesis most relevant for evaluating the data in Table?

a. There is no significant difference between the extinction rate of animals between 1950 and 2000 in China and the background extinction rate.
b. There is no significant difference between the extinction rates of mammals, birds, amphibians, and reptiles in China.
c. There is a significant difference between the extinction rate for mammals in China and the background extinction rate for mammals.
d. Because of climate change, habitat loss, pollution, and excessive exploitation of resources, China experienced a mass extinction event between 1950 and 2000.

A

Explanation:

The null hypothesis is otherwise known as the hypothesis of no difference. In other words, the null hypothesis assumes that there is no significant difference between two or more data from populations that are being statistically compared. This is as opposed to the alternate hypothesis that assumes that there is a statistically significant difference between the data from the population being compared.

In the illustration, it is clearly stated that a mass extinction event occurs when the rate of species extinction exceeds the background extinction rate. Hence, the data collected on the extinction rates of different mammals need to be compared with that of the background extinction rate, and only a significantly higher extinction rate of the animals can lead to the conclusion that mass extinction has occurred.

The null hypothesis, therefore, would be that there is no significant difference between the extinction rates of the various animals and the background extinction.

The correct option is A.

the answer is admiramos

the rule for verbs is whoever you are referring to (in this case 'nosotros'), you need to change the ending of the word.

nosotros - amos

yo - o

tu - as

el, ella, usted - a

ellos, ellas, ustedes - an

(examples: nosotros bailamos (instead of bailar) or yo hablo (instead of habla)

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.