Marine science module 2 flvs DBA question please help asap

Suppose you are estimating the size of a blue crab population. what is the population size if the number marked in the first catch is 40, the total number in the second catch is 200, and the number marked in the second catch is 50?

In eukaryotes, genetic information is passed to the next generation by processes that include mitosis or meiosis. which of the explanations identifies the correct process and supports the claim that heritable information is passed from one generation to another? a. mitosis, followed by cytokinesis, produces daughter cells that are genetically different from the parent cell, thus insuring variation within the population. b. during mitosis, dna replication occurs twice within the cell cycle to insure a full set of chromosomes within each of the daughter cells produced. c. in asexual reproduction, a single individual is the sole parent and passes copies of its genes to its offspring without the fusion of gametes. d. single-celled organisms can fuse their cells, reproducing asexually through mitosis to form new cells that are not identical to the parent cell.

What causes the force that pushes magma from the magma chamber through the pipe and vent of a volcano?