Small gaseous molecules such as ammonia, chlorine, and ethylene contain bonds.

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

Archeologists have discovered three sites showing conclusive evidence for the mastery of fire in tanzania, from a period slightly after the time that homo habilis was present in africa. these sites clearly were founded by homo erectus, the descendent species of homo habilis that migrated north, out of africa and into asia. homo erectus was known to have mastered fire, from ample evidence at sites in asia. there is no reason to attribute mastery of fire to homo ergaster, the descendent species of homo habilis that remained in africa.which of the following is an assumption on which the argument depends? (a) before their migration, homo erectus occupied african territory as far south as tanzania.(b) the strain of migration provided the selective pressure motivating homo erectus‘ mastery of fire.(c) homo ergaster would not have derived as much benefit from the mastery of fire as did homo erectus.(d) homo ergaster inherited all cultural knowledge from homo habilis, a species that did not have mastery of fire.(e) homo ergaster did not occupy regions as far south as tanzania until well after the time of these three sites.

1. you serve a volleyball with a mass of 2.1 kg. the ball leaves your hand with a speed of 30 m/s. the ball has energy. calculate it. 2. a baby carriage is sitting at the top of a hill that is 21 m high. the carriage with the baby weighs 12 n. the carriage has energy. calculate it. 3. a car is traveling with a velocity of 40 m/s and has a mass of 1120 kg. the car has . calculate it.