What is conserved in physical changes?
shape
energy
mass
density

Choose the best explanation of the difference between evolution and natural selection. a. natural selection is the idea that species change over time, and evolution is the idea that our world changes over time. b. evolution is the idea that species change over time, and natural selection is the idea that nature changes over time. c. natural selection is the idea that species change over time, and evolution is the idea that the species' food source also changes over time. d. evolution is the idea that species change over time, and natural selection is a mechanism by which evolution takes place.

What is the role of dna helicase during dna replication? a. to unwind the duplex dna b. to attach primers to the replicating strands c. to add bases in the sugar-phosphate backbone reset

Scientists have noted that at present the earth is closest to the sun in january and farthest from the sun in july. the reverse will be true in 13,000 years and theearth will then be closer to the sun in july than january. how does earth's current proximity to the sun affect the climate in the northern hemisphere? winters are cooler and summers warmer because of the closer proximity of the earth to the sun. winters are warmer and summers cooler because of the closer proximity of the earth to the sun. winters are shorter and summers longer because of the closer proximity of the earth to the sun. winters are longer and summers shorter because of the closer proximity of the earth to the sun