Scientists believe that during the late cretaceous period, many small seas dried up and new mountains began to rise. which would most likely cause them to believe the temperature decreased during this time?
a) the absence of fossils of warm-weather plants.

b) the absence of fossils of many species of fish.

c) the discovery of fossils of fish with small legs.

d) the discovery of fossils of warm-weather insects.

A) The absence of fossils of warm-weather plants

Explanation:

During the later stages of the Cretaceous period, the climate started to change. From the predominantly warm, tropical and subtropical, the climate started to have more variations, with mountainous climates starting to develop, as well as temperate climate types. This was caused by the movement of the tectonic plates, as it cause lot of changes in the landscape, positions of the continents, movement of the ocean currents, movement of the air masses. One indicator that the climate cooled down is that the fossils of tropical plants are lacking in most of the planet, and they are only limited to the lowest latitudes, while fossils from plants that are much better suited to temperate climates and colder climate are dominating.

a and c

c is 100% but i am confused in a

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