A meteorologist is 4.8 km from a thunderstorm when she sees a lightning bolt emerge from the storm. In how many seconds will she hear thunder after seeing the lightning? Assume air temperature = 20C and use eBook Table 6.1 to find the speed of sound in air at 20C.

1. Express answers to 3 significant figures unless other instructions are given in the question.

Table 6.1 Speed of Sound in Some Common Substances Speed* Substance (m/5) (mph) Air At - 20"0 320 715 At 20*C 314 770 At 40"C 356 795 Carbon dioxide 269 600 Helium 1,006 2,250 Water 1,440 5,220 Human tissue 1,540 3,450 Aluminum 5,100 11,400 Granite 4,000 9,000 Iron and steel 5,200 11,600 Lead 1,200 2,700 "At room temperature (20"C) except as indicated