Answer:
81-25k²
Step-by-step explanation:
We need to write the expression for "The quantity 81 minus 5k, squared".
Square of any number x is given by x².
Square of 5k is given by : (5k)²= 5²×k²=25k²
Now subtract 25k² from 81.
It means we get : 81-25k². It is required expression.
Answer: The total amount the water change was -28 gallons by the end of the week <u>OR</u> The total amount the water changed decreased 28 gallons by the end of the week. Depending on how you want to word it.
Hope this helps!
Step-by-step explanation:
<u>Create you equation:</u>
x = the total amount the water changed
d = the amount of days
x = -4d
<u />
<u>Insert the known information into the equation and solve:</u>
x = -4d
x = -4(7)
x = -28
The percentage of the snakes is longer than 16.6 in. with a mean of 15 in. and a standard deviation of 0.8 in. is 2.275%.
<h3>What is a normal distribution?</h3>
It is also called the Gaussian Distribution. It is the most important continuous probability distribution. The curve looks like a bell, so it is also called a bell curve.
The z-score is a numerical measurement used in statistics of the value's relationship to the mean of a group of values, measured in terms of standards from the mean.
The lengths of a particular snake are approximately normally distributed with a given mean = 15 in. and standard deviation = 0.8 in.
Then the percentage of the snakes is longer than 16.6 in. will be

Then we have

More about the normal distribution link is given below.
brainly.com/question/12421652