A cross -country skier moves from location A to location B to location C to location D . Each leg of the back -and-forth motion takes 1 minute to complete ; the total time is 3 minutes . (The unit is meters .) West East t 0min t=2min t=3min t=1min 20 60 100 120 100 160 Calculate the average speed and average velocity (in mi/hr) during the three minutes of recreation.

Location A => t=0 => 0

Location C => t=2 => 40

Location D => t=3 => 120

Location B => t=1 => 160

Total time 3min

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day