<u>Answer:</u>

<u>Solution:</u>
Given: x=30
To solve: 
On substituting the value of x,

On dividing 30 and 5 we get,

So, the option is 15.
Answer:
120
Step-by-step explanation:
All the interior angles in a regular hexagon are 120 degrees.
Two events are mutually exclusive if they cannot occur in the same trial of an experiment.
0.35x + 0.60y = 0.40(x + y) where x = vol. of 35% and y = vol. of 60%
x + y = 20
solve this system of equations
x + y = 20
-0.05x +0.20y = 0
this gives x = 16 and y = 4
so you need 16 L of 35% and 4 L of 60% solution.