Rock material moves downward in a convection current because they are: a.) hotter and less dense
b.) colder and more dense
c.) colder and less dense
d.) hotter and more dense

What is the result of the greenhouse effect? a. heat is deflected from the atmosphere. b. heat is released from the atmosphere. c. heat is kept in the atmosphere. d. plants are able to grow in the tropics where the air is the heaviest.

Paraguay is one of the only two countries in the americas that don't have a coastal border. the country is slightly smaller than california. it was under a military dictatorship for 35 years, ending in 1989; today it is a constitutional republic. most of the population is roman catholic, and over 60% of the people live in cities. its environment is threatened by deforestation and water pollution. which of the following facts from the paragraph above best describes an element of paraguay's culture? (apex)

Suggest 3 different reasons why there is an ageing population in the uk .