7Which of these do all prokaryotes and eukaryotes share? A.
nuclear envelope
B.
cell walls
C.
membrane-bound organelles
D.
cell membrane

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Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.

Explain why it’s important for scientists to study the sun. list at least two challenges researchers face when examining earth’s nearest star.