If an object's weight is what pulls objects towards planets, then what about an object can cause objects to be pulled towards planets? Answer choices: - phase - structure - Energy. - means - wind - energy - weight - sunlight
weight

If when the immune system recognizes a foreign substance, antibodies are produced, then what happens when the immune system recognizes a foreign substance? Answer choices: - an area swollen with pus - The immune system fails - irradiation - Bacteria dies - Antibodies are formed - major threat to health - Something that causes allergies - Viruses reproduce
Antibodies are formed

If food keeps mammals' metabolic rates high, then what keeps mammals' metabolic rates high? Answer choices: - gas - muscle - fur - sleep - water - Fe - food - ice
food