並前往https://www.numerade.com/ask/question/a-restriction-digest-4-marks-set-up-2-tubes-digest-30-ml-total-volume-containing-400-ng-of-pbr322-and-10-u-of-ecori-control-30-ml-total-volume-containing-400-ng-of-pbr322-but-no-enzyme-calcu-22388/