Aperson with his ear to the ground, sees a huge stone strikethe concrete pavement. a moment later two sounds are heard from theimpact: one travels n the air and the other in the concrete, andthey are 2.2 s apart. how far away did the impact occur?
*the speed of sound for air is 343 m/s, for concrete˜3000.
show how you set up the problem and how you got youranswer.

A1,200 kg car is accelerated at 3.7 m/s2. what force was needed to produce this acceleration? a. 4,440 n b. 324.3 n c. 4,388 n d. 304.3 n

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?