Answer:
He will have paddled the canoe for 4 km.
a. The distance paddled out is equal to the distance paddled returning.
Explanation:
Let d be the distance that Roger Waters paddled out.
Let t be the time for the travel he paddled out and t' be the time for returning.
Then from the formula
,
t =
and t' =
![(d)/(2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/ehh26br6yuze4ut4uexijljjq4sp87kgcb.png)
Total time for the journey = 1 hour 30 minutes = 1.5 hours
So, t + t' = 1.5
![(d)/(4) +(d)/(2) =1.5](https://img.qammunity.org/2019/formulas/mathematics/middle-school/vrzmq3uqoy8h7vew1u0me9krlx5tc35z9x.png)
![(3d)/(4) =1.5](https://img.qammunity.org/2019/formulas/mathematics/middle-school/z0qzizmc4r0mswl59uyf702stmnl6kazog.png)
3d = 6
d = 2 km
The total distance he will have paddled the canoe = 2d = 2(2) = 4 km.
Clearly, the distance he paddled out = the distance he returned.
Hence, the correct option is A.