As trees along a heavily shaded stream are cut down for farm land, the environmental protection agency (epa) must measure changes to the local stream habitat. water samples from the stream are collected over time. the microorganisms are counted and classified in order to track changes.
epa researchers most likely used a to view the microorganisms in the stream water samples.
a)
light microscope
b)
magnifying glass
c)
computer simulation
d)
scanning electron microscope

The buildup of sediments where a river empties into a slow-moving or nonmoving body of water is known as a/an

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?

A60-tooth gear is connected to a 72-tooth gear.if the smaller gear turns 12 times,how many turns does the larger gear make?