Answer:
Distance between B and C = 
Step-by-step explanation:
Let the time taken to reach from station A to B be x hr
Let the time taken to reach from station B to C be y hr
Given total time from station A to C be 6 hr
∴ x + y = 6
⇒ y = 6 - x → (1)
Also total distance given is 285 miles
As 
∴ distance travelled between station A and B
=
distance travelled between station B and station C
=
So, 40x + 55y = 285
⇒ 40x + 55(6 -x) = 285 (From 1)
=> 40x + 330 - 55x = 285
=> -15x = 285 - 330
=> -15x = -45 ⇒ x=3
gives y = 6-3 = 3 hours
Distance between B and C = 
It’s either B or C if it’s being translated to the right it’s B but if it’s being translated to the left it’s C
First you want to subtract 21.91 from 68.77 which will leave you with 46.86 then you divide 46.86 by 1.72 then you get about 27.22 so 27.20 gigs were used
B) An example..... It would be better to explain and give an example to what your trying to say.