Need answered asap for test if a chemical change requires energy, which of the following could be the source of the energy? select one: a. settling the mixture for 20 minutes b. adding more substance to the observed material c. measuring mass from a beam balance d. heating with a flame

8) warming your hands by a fire is an example if which heat transfer? a. conduction b. convection c. radiation d. none of these

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd a) 30 joules b) 3000 joules c) 320 joules d) 3200 joules

(04.05 hc) analyze the given diagram of the carbon cycle below. part 1: which compound does c represent? part 2: name a process that could release this compound into the air. part 3: explain how the elements that form it are conserved during the carbon cycle. use complete sentences to explain your answer. justify how this compound was created from a recycling of carbon in the carbon cycle. use complete sentences to explain your answer.