1. In physics, work is defined as A. force times effort B. energy expended per unit time C. energy times displacement D. force times displacement ABCD 2. In physics, a strain A. is a change in length divided by original length B. is a proportion C. is dimensionless D. all of the above ABCD 3. In physics, elastic means A. stretchy B. ability to return to original shape C. easily deformable D. plastic ABCD 4. Spider frame silk has the same tensile strength as A. Kevlar B. cotton fiber C. nylon D. human tendon ABCD 5. The greater the alignment of molecules in spider silk A. the more crystalline it is B. the more stretchy it is C. the more viscid it is D. all of the above ABCD 6. The definition of running includes A. using more energy than walking B. reaching a velocity of greater than 2.5 meters/second C. both feet off the ground simultaneously D. all of the above ABCD 7. The "spring in your step" is due to A. stretched tendons B. the elastic nature of muscle and bone C. the action of heel and toe D. the motion of hips around the pelvis ABCD 8