15. which of the following accurately reflects the beliefs on earth's early history?
a. scientists believe that microspheres nearly prevented the development of early life.
b. scientists believe oxygen was plentiful in the early atmosphere.
c. scientists believe the early atmosphere lacked the oxygen necessary to support modern human life.
d. scientists believe that dna may have existed before rna

Hydrilla (hydrilla verticillata) is an invasive aquatic plant and one of the most serious aquatic pests in florida. hydrilla has already been introduced to hundreds of bodies of water throughout florida, hydrilla is difficult to control because it grows rapidly and survives in many different water depths and conditions. hydrilla • describe how hydrilla affects native plant and animal species. include both a biotic and an abiotic limiting factor. • suggest one biotic and one abiotic recommendation that could slow the spread of hydrilla

Match the functions to the cell types ? contraction and relaxation. conducting electrochemical signals fighting diseases carrying genetic material

What are 3 reasons that natural selection occurs