Answer:
conserving water is important because it keeps water pure and clean while protecting the inviorment
By definition we have that the density is given by:

Where,
M: mass of the sample
V: volume occupied by the sample
Therefore, substituting values in the given equation we have:


Answer:
the density of a sample of gas with a mass of 30 g and a volume of 7500 cm3 is:

The mirror formula for curved mirrors is:

where
f is the focal length of the mirror

is the distance of the object from the mirror

is the distance of the image from the mirror
The sign convention that should be used in order to find the correct values is the following:
-

: positive if the mirror is concave, negative if the mirror is convex
-

: positive if the image is real (located on the same side of the object), negative if it is virtual (located on the opposite side of the mirror)
A potential problem is that you are willing to accept a <u>5% </u>chance of being wrong if you reject the null hypothesis.
The significance level is the probability of rejecting the null hypothesis if it is true. For example, a significance level of 0.05 indicates a 5% risk of concluding that there is a difference when there is actually no difference. Rejecting the true null hypothesis results in a Type I error.
The smaller the value of α the more difficult it is to reject the null hypothesis. Therefore, choosing a low value for α can reduce the likelihood of Type I errors. The result here is that if the null hypothesis is false, it may be more difficult to reject using a lower value for α. The alpha value or statistical significance threshold is arbitrary. Which value to use depends on your field of study.
Learn more about The potential problems here:-brainly.com/question/21836542
#SPJ4
Based on the description, it will be most likely that he believes in Oscillating model (also known as Cyclic model) of the universe
Based on this model, the gravitational force will prevent further expansion by pulling back the matters and undergo a bounce
hope this helps