Bianca is standing at x =600m. firecracker 1, at the origin, and firecracker 2, at x =900m, explode simultaneously. the flash from firecracker 1 reaches bianca's eye at 4.0 μs . part a at what time does she see the flash from firecracker 2?

Explanation:

Given

Bianca is at

i.e. distance between origin and Bianca is

time taken to reach Bianca eyes is

i.e. Cracker exploded at because it is observed at

Time taken by second cracker flash to reach Bianca eyes

Therefore it will be observed at

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)