| A | B |
| The age of the Earth | 4.5 - 4.6 billion years |
| The rotation speed of Earth | is slowing |
| Greenland calves about | 16,000 icebergs each year |
| Eating disorders: | Anorexia, Bulimia & Compulsive Overeating |
| An understanding of Ecology | requires interdisciplinary studies |
| Amino acids | chief components of protein |
| Energy | the ability to do work |
| Enzymes allow the cell to | carry out chemical reactions quickly |
| Soil erosion can be retarded | by using mulch |