1. The problem statement, all variables and given/known data 2. Relevant equations no equations needed b/c its a conceptual question. 3. The attempt at a solution my attempts.. A) the earliest it can occur and can only be connected by speed of light there t2= 1200/3*108=4*10-6.. B) yes it can because event(E0) occurred 1micro sec before event E1, there E0 could trigger event E1 I'm partly sure I'm correct but i need someone to verify.. thanks in advance!