Which of the statements about elements is true? a) the atoms of all elements have different mass, but same volumes. b) the atoms of all elements have the same mass and volume. c) scientists have identified a little less than 100 elements. d) no two elements have the same kind of atom.

During spring semester at mit, residents of the parallel buildings of the east campus dorms battle one another with large catapults that are made with surgical hose mounted on a window frame. a balloon filled with dyed water is placed in a pouch attached to the hose, which is then stretched through the width of the room. assume that the stretching of the hose obeys hooke's law with a spring constant of 89.0 n/m. if the hose is stretched by 5.80 m and then released, how much work does the force from the hose do on the balloon in the pouch by the time the hose reaches its relaxed length? unitst 3 number-1497 the tolerance is +/-5% open show work click if you would like to show work for this question:

Free runners jump long distances and land on the ground or a wall. how do they apply newton’s second law to lessen the force of impact?

How is sound energy produced a. vibrating objects b. objects being heated c. temperature differences d. stationary objects