This is possible because when a star dies, it basically expands to its maximum (explodes). Therefore, the materials of the exploded star mix with the primeval hydrogen of the Universe. Later, other stars are formed out of this mixture. Thats also how the sun was formed. :)
Yogurt can stay good after 2 hrs of being in room temperature.
The heat from hotter object goes to the cooler object. when they reach the same temperature the heat flow will stop.
Prokaryotes do not contain membrane, and eukaryotes do contain membrane.