An experimenter arranges to trigger two flashbulbssimultaneously, a blue flush located at the origin of hisreference frame and a red flush at x $=30\mathrm{.}4$ km$.$ A secondobserver$,$ moving at speed $0\mathrm{.}247$c in the direction ofincreasing x$,$ also views the flushes.$($a$)$ What time interval between them does she find?$($b$)$ Which flush does she say occurs first?