Students planted three bean seeds. after several days, they observed that the seeds' roots were growing downward into the soil. which type of topism were the roots displaying?

The table below shows the elements that mainly comprise each of the four layers of earth: elements in layers layer main elements crust oxygen, silicon mantle iron, magnesium outer core iron, nickel inner core iron which of these elements make up the layer that is 0.2 to 1.1 percent of earth's total diameter?