What is the main advantage of a reflecting telescope design?

Which statement describes john tuzo wilson’s contribution to the theory of plate tectonics? he proposed that plates carry parts of the seafloor. he theorized that pieces of earth move for a limited time. he suggested that the asthenosphere is broken into segments. he observed seafloor cracks similar to existing cracks in the continents.

Agricultural practices in the united states nearly led to the extinction of the peregrine falcon during the 1950s and 60s.

In the diagram below, ab and bc are tangent to o. what is the measure of