HELP ASAPP!! I have no idea and I don’t have much time left

Look at the figure above. which atmospheric layer has around 80 percent of the mass of the earth's atmosphere? (hint: it's where the clouds seen on earth are formed.) a. exosphere b. troposphere c. stratosphere d. thermosphere

Place the steps tor the formation of the enzyme pepsinogen in correct order

Which of these is true of the cytoplasm of an unfertilized egg? a. it is an unevenly distributed mixture of mrna, proteins, organelles, and other substances. b. it does not contain substances that are important in directing development. c. these substances are supplied by the sperm. d. it does not contain substances that are important in directing development. e. development is directed solely by the surrounding cells. f. it is a homogeneous mixture of mrna, proteins, organelles, and other substances. g. it does not contain substances that are important in directing development. h. these substances are produced by the dna of the fertilized zygote.