sound travels at a rate of about 1.1*10^3 feet per second. Suppose a mining company detonates a bundle of dynamite at a distance of 625 feet from a canyon wall. At the time of a detonation the miners sit safely at a distance of 2,600 feet from the dynamite. How long after detonation will the miners hear the echo of the blast off the canyon wall? Round to the nearest tenth if necessary.
