(Q).
Q: Huge calderas form when the mountain above an empty chamber of what collapses? Read this paragraph and choose the correct option from the provided answers: During a massive eruption, all of the material may be ejected from a magma changer. Without support, the mountain above the empty chamber may collapse. This produces a huge caldera . Calderas are generally round, bowl-shaped formations ( Figure below ). Choices: - gas - mercury - coal - magma A:
(A).
magma

(Q).
Q: Steam consists of what common and essential element in its gaseous phase? Read this paragraph and choose the correct option from the provided answers: Choices: - carbon dioxide - air - plasma - water A:
(A).
water

(Q).
Q: Chemical reactions always involve energy. when methane burns, for example, it releases energy in the form of what? Read this paragraph and choose the correct option from the provided answers: Chemical reactions always involve energy. When methane burns, for example, it releases energy in the form of heat and light. Other chemical reactions absorb energy rather than release it. Choices: - movement and light - light and sound - heat and movement - heat and light A:
(A).
heat and light