Two spaceships a and 8 are moving in opposite directions. each measures the speed of the other to be (3js)e. they pass alongside each other and each sets its clocks to zero at that instant. ship a receives a light-message at time t = 320 hours on its clocks that there has been an explosion in 8 that destroyed 8's oxygen generating plants and also left them unable to alter their velocity. the occupants of8 know that they have only enough oxygen to survive 1000 hours (on 8 's clocks). ship a, immediately upon receiving the message, sends rescue ship c to b. the velocity ofc, as measured by a, is (4js)e. assume that 8 sent the message simultaneously with the explosion and that c was dispatched simultaneously with the receipt of the message by a. (a) how long must the crew of8 wait for rescue, according to a, from the time of the explosion to the time that c arrives? (b) how long is this time interval according to the clocks of 8? were they rescued or not? hint: start by drawing a sequence of four pictures in a's rest frame, each picture representing an important event in the story.