A stone is dropped into a deep canyon and is heard to strike the bottom 6.91 s after release. How deep is the canyon? The speed of sound waves in air is 343 m/s and the acceleration of gravity is 9.8 m/s 2 . Answer in units of m.

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

What can be found in every skeletal muscle? a. nerves, bones, cartilage, and connective tissue b. tendons, cartilage, nerves, and blood vessels c. muscle fibers, nerves, connective tissue, and blood vessels d. tendons, nerves, blood vessels, and bones

Could someone me find the answer to this problem.