How are atoms, elements and compounds related ?

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.

This is collection of data made by comparing objects in standard units. in science, the units are metric.