During pregnancy under what condition is Rh incompatility a problem

Were does condensation occur? a) hydroshereb) lithosherec) boishered) atmosphere

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins

At which point is crust neither created nor destroyed? island chain mid-ocean ridge divergent boundary transform boundary