A mid-ocean ridge forms from ____plates.

• separating
• volcanic
• sliding
• colliding

____ acts on mountains to change their size, height, or surface.

• Slipping
• Erosion
• Shifting
• Sliding

Mountains made of huge rocks separated from other rocks by faults are ____ mountains.

• folded
• volcanic
• fault-block
• upwarped

Tremendous pushing forces cause a squeezing of rock layers in ____ mountains.

• fault-block
• folded
• upwarped
• volcanic

Plates move apart because of ____, a pulling force acting on plates.

• volcanoes
• tension
• faults
• rifts

When forces inside Earth push up the crust, ____ mountains form.

• volcanic
• fault-block
• upwarped
• folded

When a plate at a mid-ocean ridge responds to gravity by sliding down a slope, it is called ____.

• slab-pull
• slab-push
• ridge-push
• ridge-pull

When plates _____, the tremendous forces mountains to form.

• collide
• subduction
• isostasy

____ is when one plate sinks beneath another plate.

• collide
• subduction
• isostasy

The principle of _____ states that Earth's crust and lithosphere float on the upperpart of the mantle.

• collide
• subduction
• isostasy