What is released when an excited electron returns to a lower energy state?
an isotope
a proton
electricity
electromagnetic radiation

The rapid decomposition of organic matter produces evidence which supports: the slow accumulation of coal deposits long ages of the earth rapid burial of vast amounts of vegetation biblical account of noah's flood

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic

Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2