Earth is made up of ________ layers.

• 1

• 3

• 4

• 6

True or False: Earth’s crust is one solid piece.

• True

• False

Volcanic eruptions are caused by

• gravity.

• pressure.

• explosions.

• Earth's rotation.

Where do volcanoes usually form?

• within 10 miles of the ocean

• between Earth’s mantle and core

• at fault lines between tectonic plates

• within the boundaries of the United States

Magma is made up of ________ from the mantle mixed with hot gas.

• lava

• plasma

• hot water

• molten rock

Which part of a volcano does magma spill out of?

• base

• crater

• shield

• mantle

What is magma called when it reaches Earth’s surface?

• lava

• molt

• crater

• shield

The Hawaiian Island volcanoes were formed by a

• hot spot.

• fault line.

• meteor.

• crater.

There are two main types of volcanoes: shield and

• dome.

• auxiliary.

• synthetic.

• composite.

________ volcanoes are no longer connected to a source of magma.

• Active

• Shield

• Extinct

• Dormant