A standard showe head uses 18 gallon of water in 3 minutes. If 270 gallons were used, how many minutes were spent in the shower?

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.