Cobalt-60 decays into nickel-60 via beta decay with a half-life of 5.27 years. A purse sample of cobalt-60 is prepared, with no contamination of other isotopes. After 5.27 years, what is the ratio of cobalt-60 to nickel-60 in the sample?

Compare the valence electron configuration of the nobles gas elements seen here. what statement is correct?

All motion is caused by force? true or false

La reaccion entre monoxido de nitrogeno (no) y oxigeno para formardioxido de nitrogeno (no2) es un paso determinante para la formacion del smog, la reaccion es la siguiente: 2no + o2 = 2no2 cual sera el numero de moles de no2 que se formaran por la reaccion completa de 8 moles de oxigeno con suficiente monoxido?