How many endings?

Why can earthquakes be a warning that a volcano is about to arupt? Would you expect hexane to be soluble in water? What is meant by malleable brittle state conductor of heat and lustre when it comes to elements? What lived 2 billion years ago? Why does penicillin mold occasional grow in jelly? What is the science of tree ring dating called? What does a photocell do? What are the three most electronegative atoms on the periodic table? storm doors for hurricane safety? One similarity between natural selection and genetic drift is that both events change what? What is an example of a glacier moving boulder? What is a tiny packet of energy released when an electron returns to a lower energy level? What is sometimes called the allocation unit? Why is decomposition important in a forest ecosystem? Do you expect paper clips to be attracted or not a attracted to a magnet? Where does the majority of the mass of a plant come from? Materials bulldozed at the front of the glacier form a .? Is larkspur an invasive species? Is the cell meembrane capable of receiving and recognizing chemical signals? What coins can be attracted to magnets?