It always travels at 3×108 m/s.

Her average speed is 94 km/h

Time taken is 3.5 hours

Step-by-step explanation:

Let Evan’s average speed be x km/h.

now since Meghan drove faster, according to the question, we can say her average speed would be x + 6 km/h

Mathematically, time = distance/speed

so; since time is the same; we have

308/x = 329/(x + 6)

cross multiply

329(x) = 308(x + 6)

329x = 308x + 1848

329x-308x = 1848

21x = 1848

x = 1848/21

x = 88 km/h

Meghan average speed = x + 6 = 88 + 6 = 94 km/h

Time taken would be 329/94 = 3.5 hours