Mét nåi h¬i b»ng thÐp cã khèi l-îng lµ 900 kg. Nåi h¬i chøa 400 kg n-íc. Gi¶ sö hiÖu suÊt sö dông nhiÖt cña nåi h¬i lµ 70%. CÇn bao nhiªu calo nhiÖt ®Ó n©ng nhiÖt ®é cña
nåi h¬i tõ 100C lªn 1000C, biÕt nhiÖt dung cña thÐp lµ 0,11 kcal/kg vµ cña n-íc lµ 1 kcal/kg

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

Which of the following best describes the formation of plasma?

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.