(10 pts, 5 pts each) Parts (i)-(ii) refer to the following spacetime diagram where an observer at rest observes a series of explosions. ct ct' Observer at Rest Moving Observer X' X (i) In the observer's frame the explosions occur: a) at the same location but at different times. b) at the same location and at the same time c) at different locations but at the same time. d) at different locations and at different times. (ii) In the moving observer's frame, indicated by the primed coordinate system, the explosions occur: a) at the same location but at different times. b) at the same location and at the same time c) at the different locations but at the same time. d) at different locations and at different times