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3 years ago

What does it mean when to say that mass is coserved during a physical change?

1 answer:

4 0

During a physical change, the mass is conserved because it isn't permanently changed, like a chemical change. A chemical change would be something like burning a piece of paper, and a physical change would be something like cutting up pieces of paper (can be put back together).

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Chad has $420 to invest. the price of a stock is $6.82 per share. what is the greatest number of whole shares chad can buy?

Nezavi [6.7K]

This is an easy question. you just have to divide.
420÷6.82= 61.5
but because they are individual stocks and you can't have half a stock, you round it up to the nearest whole number
so the answer is 61
hope I helped:)

5 0

3 years ago

The professor informs the class that there will be a test next week. what is the probability that a randomly selected student st

marusya05 [52]

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):

$S|B = \frac{B|S \times S}{B|S \times S\; +\; B|S' \times S'} \\\\S|B = \frac{0.55 \times 0.6}{0.55 \times 0.6 \;+ \;0.2 \times 0.4}\\\\S|B =\frac{0.33}{0.33 + 0.08} \\\\S|B =\frac{0.33}{0.41}$

S|B = 0.80.

Read more on probability here: brainly.com/question/25870256

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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.

5 0

2 years ago

One mole of potassium permanganate kmno4 contains grams of oxygen.

Pepsi [2]

1 mol KMnO₄ contains 4 mol O, which has a molar mass of about 15.999 g/mol. Then the mass of O in the sample is

(4 mol) (15.999 g/mol) ≈ 63.996 g

8 0

2 years ago

The image produced by an object is –10. 0 cm from a concave mirror that has a focal length of 5. 0 cm. The distance of the objec

Anon25 [30]

The distance of the object from the mirror is 3cm.

To calculate the distance of the object from the mirror, we make use of the mirror formula

<h3>Mirror formula</h3>

1/f = (1/u)+(1/v)............ Equation 1

Where:

f = Focal length of the mirror
v = image distance
u = object distance.

Using the real is positive convention,

Given:

f = 5 cm
v = -10 cm

Substitute these values into equation 1 and solve for u

1/5 = (-1/10)+(1/u)
1/5+(1/10) = 1/u
1/u = (2+1)/10
1/u = 3/10
u = 10/3
u = 3.33
u = 3 cm

Hence, The distance of the object from the mirror is 3cm.

Learn more about mirror formula here: brainly.com/question/26257987

7 0

2 years ago

a model that shows the many interconnected feeding relationships in an ecosystem is a food . ( only use one lower case word )

lorasvet [3.4K]

Answer:

food web

Explanation:

it shows the interconnected relationships, and it also shows the trophic level for the following organism

8 0

2 years ago