60 minutes=1 hour
360 minutes=6 hours
so 360 minutes/90 minutes
so your answer is 4 hours
Answer:
- <em>0.75</em><em> liters of 5% hydrochloric acid solution </em>
- <em>0.25</em><em> liters of 45% hydrochloric acid solution.</em>
Step-by-step explanation:
Let us assume that, x liters of the 5% hydrochloric acid and y liters of the 45% hydrochloric acid solutions are combined.
As Rajan need total of 1 liter of solution, so
i.e
--------------------1
As Rajan needs 5% hydrochloric acid and 45% hydrochloric acid to make a 1 liter batch of 15% hydrochloric acid, hence acid content of the mixture of two acids will be same as of the final one, so

i.e
-------------2
Putting value of x from equation 1 in equation 2,





Putting the value of y in equation 1,

Therefore, Rajan must use 0.75 liters of 5% hydrochloric acid solution and 0.25 liters of 45% hydrochloric acid solution.
1. b 2. a 3. a
100% correct edge 2021
Step-by-step explanation:
Answer:
18x^2 - 9
Step-by-step explanation:
y = f(x)= 6x^3 - 9x + 4
dy/dx = d/dx(6x^3) - d/dx(9x) + d/dx (4)
=6.d/dx(x^3) - 9.d/dx (x) + d/dx. (4)
=6.3x^2 - 9.1 + 0 =18x^2 - 9
Answer:
(47.3, 54.1)
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.96.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 50.7 - 3.4 = 47.3
The upper end of the interval is the sample mean added to M. So it is 50.7 + 3.4 = 54.1
The answer is (47.3, 54.1).