Electrical engineers have a device that tests for battery life (inminutes) by placing a battery under a controlled electrical load and measuring how long it lasts.They are interested in comparing the performance of 4 brands of batteries.They replicated theexperiment 4 times by randomly assigning a battery brand to be used in the electrical load deviceeach time they measured battery life.In other words, they made 16 'runs' and randomized theorder in which the battery brands were used