When did oxygen levels start to decline from 35 percent down to today's levels?

Advanced Placement (AP)

2 answers:

lara31 [8.8K]3 years ago

7 0

A. after the carboniferous period

Readme [11.4K]3 years ago

4 0

Oxygen levels start to decline from 35 percent down to today's level after the carboniferous period.

Answer: Option a

<u>Explanation: </u>

The Pangea formation marked the carboniferous period. Pangea has revolutionized land and sea, laying the foundations for new species of plants and animals. A new group of species, diapsids, enters the stage.

During the carboniferous period, 35 percent of oxygen levels began to fall to current levels. Oxygen levels dropped from 35 percent to their current level about 95 million years ago. Oxygen is a product produced as waste from photosynthesis and used by respiration.

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If the wait time is less than 30 minutes for 75% of all patients in the emergency room, what is the probability that the

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<h3>What is probability? </h3>

Probability can be defined as the likelihood of an event to occur. In statistics, the mean of the sample distribution typically shows the probability of the population.

From the parameters given:

The sample size (n) = 55 patients
Let's assume that the mean (x) = 32 (i.e. 58.2%) of the patients

The sample proportion $\mathbf{\hat p}$ can be computed by using the expression:

$\mathbf{\hat p = \dfrac{x}{n}}$

$\mathbf{\hat p = \dfrac{32}{55}}$

$\mathbf{\hat p =0.582}$

If the percentage of the probability of all patients in the emergency room = 0.75

The probability that the proportion of patients who wait less than 30 minutes is 0.582 or less can be computed as:

$\mathbf{( \hat P \leq 0.582) = P \Big( \dfrac{\hat p - p}{\sqrt{\dfrac{p(1-p)}{n}}} \leq \dfrac{0.582 - 0.75}{\sqrt{\dfrac{0.75(1-0.75)}{55}}} \Big )}$