Earth’s largest ecosystems are the?

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

This is a situation in which genes are attached to an organism's sex chromosomes; the sex of an organism influences the expression of a gene.

Rarefaction is used for which of the following? a. creating a representative sample b. studying how disease impacts populations c. rediscovering species thought to be instinct d. determining which sea creatures live in an area