What indicates that a b cell or t cell has developed immunocompetence?

Witch type of microscope is used to view very small cell components like proteins and dna?

There is a liquid capsule inside a cup full of liquid. the cup full of liquid has salt in it and the liquid capsule has no salt in it. in which direction will the solvent flow? a. the salt does not have to move b. from the capsule to the larger cup c. equally between the capsule and the cup d. from the larger cup to the capsule

Identify the composition of oceanic and continental crystal rocks.in a model of earth’s interior,where would these rocks appear?