If chrissie shirks additional work given to her what trait does she lack

Which of the following statements is true of cells

The part of the eye that closes and opens to let light in is .

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?