The probability that students who were randomly selected studied for the test, if they pass it with a B or higher grade is: D. 0.80.
<h3>How to calculate the probability?</h3>
In this exercise, you're required to determine the probability that students who were randomly selected studied for the test, if they pass it with a B or higher grade. Thus, we would apply Bayes's theorem.
- Let S represent studied for.
- Let B represent a score of B or higher grade
Therefore, we need to find P(S|B):

S|B = 0.80.
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<u>Complete Question:</u>
At the beginning of the semester, a professor tells students that if they study for the tests, then there is a 55% chance they will get a B or higher on the tests. If they do not study, there is a 20% chance that they will get a B or higher on the tests. The professor knows from prior surveys that 60% of students study for the tests. The probabilities are displayed in the tree diagram.
You know inglés to translate? Maybe I can help you
Answer:There are numerous reasons why soils differ regionally. The most influential factors include the parent material (the rocks from which the soil has come), the climate and terrain of the region, as well as the type of plant life and vegetation present, and, of course, human influence.
Explanation:hope this helps
The magnitude of the force of the elevator floor on the person is; 807.13 N
<h3>What is the Magnitude of force? </h3>
We are given;
Weight; W = 0.7 KN
Acceleration; a = 1.5 m/s²
There are only two forces acting on the person: which are his weight W (downward) and the normal force N of the floor against the body (upward). Thus the equilibrium equation here is;
N - W = F
N - W = ma
Here, m is the mass of body, and its value is calculated as;
W = mg
0.7 = 9.81m
m = 0.7/9.81
m = 71.42 kg
Thus;
N - 0.7 = 71.42 * 1.5
N = 0.7 + (71.42 * 1.5)
N = 807.13 N
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