What are the main causes of crack growth in rocks overtime

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

Name three populations commonly found in a prairie system

Ominge cade de la inaptimea de 3 metri apoi sare de la podea pina la inaltimea de 0,5 metri. determina a) forma traectoriei mingii. b) deplasarea mingii. c) drumul parcurs de minge. va rog foarte mult va dau coroana