A ____ occurs when magma comes near water or into contact with it.

A _______ is a type of hot spring where water shoots out into a calm pool.

A _______ occurs when part of a volcano collapses and cause a rapid downhill movement of rock and soil.

__________ is formed when gases mix with water in the air.

A ________ is a dense cloud of superheated gases and rock fragments that move quickly downhill from an erupting volcano.

_____________, which occur when magma contacts water, can be devastating.

Hot springs and ________ are the result of surface water being heated by magma.

True or false: Lava flows are not harmful because they move slowly.

True or false: Volcanic mudflows are especially likely in dry areas.

True or false: Underground water heated by magma can be used to provide energy at the Earth's surface.

True or false: One effect of volcanic activity on air is that it adds dangerous gases to the air.