A chemist mixes 10 liters of 20% solution with x liters of a 35% solution. Which of the folling expressions represents the total number of liters in the mixture?

The construction of copying qpr is started below. the next step is to set the width of the compass to the length of ab. how does this step ensure that a new angle will be congruent to the original angle? by using compass take the measures of angle and draw the same arc according to it.