Emilio is at an observatory and is examining a newly discovered star through a powerful telescope. He wants to find out how bright the star actually is. What information does he need to be able to determine the absolute brightness of the star?
Color and distance from Earth to the star
Color and temperature of the star.
Color and composition of the star
Apparent magnitude and distance from Earth to the star.

In which situations is the principle of cross-cutting relationship useful in determining relative age?

Select the word from the list that best fits the definition a system made of 25 satellites

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.