Which chemical weathering process involves the action of carbonic acid on rocks such as limestone that are composed of calcium carbonate?

Oxidation

Hydration

Solution

Carbonation

Describe two recent or ongoing space missions.

Select the word from the list that best fits the definition the temperature to which air must cool to be saturated

Imagine a self-reactive t cell that has not undergone clonal deletion in the thymus (that is to say, it has escaped central tolerance). if it encounters self antigen in the absence of an infection or inflammation, what will happen to this self-reactive t cell? (select two answers) (a) the t cell undergoes clonal expansion. (b) the t cell gains effector functions. (c) the t cell undergoes apoptosis. (d) the t cell becomes activated. (e) the t cell becomes anergic.