Consider the gravity of the four spheres. If we wanted sphere C to attract the oth
sphere C we must change?

Did you know that there are 4 spheres of earth that all interact together? ... The four spheres are the geosphere (all the rock on Earth), hydrosphere (all the ... to effect Earth's systems and processes, and they are constantly changing each other. ... car means additional resources from Earth's spheres do not have to be used.

Explanation:

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

c. magnitude and direction