STEPS:
Place compass point on the vertex of the angle (point B).
Stretch the compass to any length that will stay ON the angle.
Swing an arc so the pencil crosses both sides (rays) of the given angle. ...
Place the compass point on one of these new intersection points on the sides of the angle.
Answer:
b=40-5a/2
Step-by-step explanation:
5a+2b=40
2b=40-5a
b=40-5a/2
pls mark brainliest
Answer:

And for this case we can use the complement rule and the normal standard distribution of excel and we got:

Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the heights of a population, and for this case we know the distribution for X is given by:
Where
and
And we select a sample size of n =70
From the central limit theorem (n>30)we know that the distribution for the sample mean
is given by:
And we want to find this probability:

And we can use the z score formula given by:

And using this formula we got:

And for this case we can use the complement rule and the normal standard distribution of excel and we got:

Answer:
S is not the subspace of 
Step-by-step explanation:
Let us suppose two vectors u and v belong to the S such that the property of xy≥0 is verified than
![v=\left[\begin{array}{c}0 \\1\end{array}\right]](https://tex.z-dn.net/?f=v%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D0%20%5C%5C1%5Cend%7Barray%7D%5Cright%5D)
Both the vectors satisfy the given condition as follows and belong to the S

Now S will be termed as subspace of R2 if
- u+v also satisfy the condition
- ku also satisfy the condition
Taking u+v
![u+v=\left[\begin{array}{c}-1 \\0\end{array}\right]+\left[\begin{array}{c}0 \\1\end{array}\right]\\u+v=\left[\begin{array}{c}-1+0 \\0+1\end{array}\right]\\u+v=\left[\begin{array}{c}-1 \\1\end{array}\right]](https://tex.z-dn.net/?f=u%2Bv%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D-1%20%5C%5C0%5Cend%7Barray%7D%5Cright%5D%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D0%20%5C%5C1%5Cend%7Barray%7D%5Cright%5D%5C%5Cu%2Bv%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D-1%2B0%20%5C%5C0%2B1%5Cend%7Barray%7D%5Cright%5D%5C%5Cu%2Bv%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D-1%20%5C%5C1%5Cend%7Barray%7D%5Cright%5D)
Now the condition is tested as

This indicates that the condition is not satisfied so S is not the subspace of 
Answer:
$1.25
Step-by-step explanation:
$2.50 / 2 = $1.25 per liter