Drag each label to the correct location on the chart. Sort the questions based on whether they are better answered by an observational study or a controlled experiment.
How effective is a new
toothpaste in reducing
cavities?
How does the daytime
temperature affect the
formation of dew at night?
Which is a better absorber
of heat, an object painted
black or the same object
painted white?
Can plants prepare food
even in artificial light?
Why does a rolling ball slow
down as it moves?

d.7.5cm is your answer

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

because if the tool that you are using is not balanced it there would be false mass.