"A rule of thumb for estimating the distance in kilometers between an observer and a lightning stroke is to divide the number of seconds in the interval between the flash and the sound by 3. Is this rule correct? 1. No; the speed of sound varies rapidly with altitude. 2. Yes; the speed of light is much greater than the speed of sound. 3. Yes; the sound waves are longitudinal waves. 4. No; the speed of light must be considered in this problem".

Explanation:

The velocity of sound depends upon temperature . The temperature is different at different altitudes .

The velocity of sound has no effect of pressure . Thus at  different altitudes , if pressure is different , it makes no difference .

Therefore the speed of sound varies rapidly with altitude , due to variation of temperature .

It also depends on the nature of medium . which also varies with altitude .

Moreover we cannot get distance by dividing time interval with 3 .

answer; i believe the correct answer is (40,000 j) good luck

+15-35=-20

going in opposite directions