Which of the following factors could explain a gradual warming trend in a planet's climate?
a) a decreasing albedo.
b) a decrease in the amount of greenhouse gases.
c) a decrease in the brightness of the sun.
d) a major volcanic eruption that increases the albedo of the planet by making clouds.
e) none of the above.

The primary agent of contact metamorphism is

What first caused people to consider that the continents were once one large landmass?

When volcanoes erupt, magma (hot, molten rock) rises toward the surface of the earth. as magma cools, solid rock forms. this rock contains substances from the interior of the earth. which of the following natural resources is likely to be plentiful near subduction zones where volcanic activity has occurred in the past?