Groups of fossil plants and animals follow each other in a definite and determinable order, and any period of geologic time can be recognized by its respective fossils. This is a statement of the . law of superposition

principle of cross-cutting relationships

principle of fossil succession

principle of original horizontality

The need activity of the nurse is to suction discharges from the trachea. current treatment approaches in the pressing consideration facilities or crisis offices are corticosteroids and nebulized epinephrine; steroids have demonstrated advantageous in extreme, direct, and even gentle croup. in the clear instances of croup, anti-microbials are not endorsed, as the etiology is viral