A tiny seeding grows into a tall tree with a mass of several tons. From where does the tree gain all that mass?

What causes darkening of the skin as melanin production increases

How much time has elapsed from the very beginning of "the memior of the conquistador bernal diaz del castillo" to the end? a. castillo's whole life b. a quarter of an hour c. a few weeks d. a decade

Dna and rna share a number of similarities, but they also differ in certain aspects of their structure. wich nitrogenous base is found in rna but is not found in dna