If nuclear fission can be used to heat buildings, then which of the following is sometimes used to indirectly heat buildings? Answer choices: - hydrogen and oxygen - carbon monoxide - direct energy - dropping spheres - electromagnetic energy - a hydraulic system - nuclear fission - farm animals
nuclear fission

(Question)
If contact between rocks is erosion, then what is erosion? Answer choices: - moonlight - looseness of dirt or compost - permineralization - water vapor - fog - The area was once underwater - fissures of hot, acidic water - contact between rocks
(Answer)
contact between rocks

Ques: If heat from the sun helps frog eggs survive and hatch into tadpoles, then what heats frog eggs so that they may hatch into tadpoles? Answer choices: - sun's heat - heat - the sun - geothermal vents - Cooking - the mother frog - the father frog - sunlight
Ans: the sun

(Q).
If dogs use hearing to sense sound, then how do dogs sense sound? Answer choices: - Heart rate - observe it - sight - hormones - waves - touch - hearing - smell
(A).
hearing

Ques:If lymphocytes are the key cells involved in an allergy attack, then what are the key cells in an allergy attack? Answer choices: - layers of fat - Lymphocytes. - fur and fat - bone cells - muscle cells - the skin - Red blood cells - animals

Ans:Lymphocytes.

If water from the air is when it changes from gas into a liquid by reducing heat energy, then water from the air occurs when it changes from gas into a liquid by reducing what? Answer choices: - direct energy - Energy. - Time and energy - kinetic energy - heat energy - energy - warmth - Temperature
heat energy