Answer:
A) 0.05
Step-by-step explanation:
Let's summarize into an equation the information we can get from that table.
We have 4 liters of an acid of an unknown concentration, let's call it (4x).
We have 10 liters of an acid with known concentration of 0.40.
And we have a total of 14 liters overall with a concentration of 0.3o.
That's like a weighted average formula: 4x + 10 y = 14z
Let's replace the concentration values we know and solve this:
4x + 10 (0.4) = 14 * 0.3
4x + 4 = 4.2
4x = 0.2
x = 0.05
So, the concentration of the 4 liters of acid on concentration X are in fact of concentration of 0.05.
24 feet by 15 feet
You divide each nukber by 5 bevause that is the given scale factor.
For an amount of sales of $5,000, the two salary choice will be equal
Let the amount of sales be $x
The 3% she will receive will be;

We add this to the base salary and equate to the former monthy salary
We have this as;
Length = x + 2 (because it is 2 cm more than x)
Width = 2x - 5 (5 cm lest than 2x)Area = 54 cm2 this is the formula to find the area Length × Width = Area (x + 2)(2x - 5) = 542x2 - x - 10 = 54 (this is you area)
Subtract 54 on both sides of equation to make the right side zero. 2x2 - x - 64 = 0 then use the quadratic formula x = (-b ± √(b2 - 4ac)) / 2a where:a = 2b = -1c = -64 Plug in these values into the formula. x = (1 ± √(1 - 4(-128))) / 4 x = (1 ± √(513)) / 4 x = (1 ± 22.65) / 4 x = (1 + 22.65) / 4 and x = (1 - 22.65) / 4 x = 5.91 and x = -5.41 Check the validity of the x values by adding them to the length and width. If the length or width should be a negative value, then that value of x is not acceptable. Now x = 5.91 Length = 5.91 + 2 (positive value.)Width = 2(5.91) - 5 ( positive value.) x = 5.91 If we look at this -- x = -5.41, Both length and width will be negative values. We reject this value of x. The answer is x = 5.91
Hope I helped and sorry it was really long