Aye
Q5 multi choice asks which has the greatest travel time yeah. And all the intervals are equal distance. And if velocity is greater at larger radii then the “greatest travel time” would be the lowest velocity coz t = d/v … so ain’t the answer B (not D)
let r(t) in y comp = zero and hence this is equal to zero then you get like 9/4t = 1-e^-4t meaning its where the two graphs intersect... then substitute t = 2.25 into r(t) horizontal component