Alkali metals alkaline earth metals and halogens and noble gases. I’m pretty sure
initial speed of the stuntman is given as

angle of inclination is given as

now the components of the velocity is given as


here it is given that the ramp on the far side of the canyon is 25 m lower than the ramp from which she will leave.
So the displacement in vertical direction is given as



by solving above equation we have

Now in the above interval of time the horizontal distance moved by it is given by


since the canyon width is 77 m which is less than the horizontal distance covered by the stuntman so here we can say that stuntman will cross the canyon.
Answer:
141.14098 secs
Explanation:
Time taken to see the lightning flash can be gotten from:
Velocity = distance/time
Time = distance/velocity
Time = (47 * 1000)/(3 * 10^8)
Time = 0.0001567 secs
Time taken to hear the thunder can be gotten from:
Velocity = distance/time
Time = distance/velocity
Time = (47 * 1000)/(333)
Time = 141.14114 secs
The time lapse between the lightning flash and the thunder will be:
141.14114 - 0. 0001567
= 141.14098 secs
The properties of the wave don't determine its speed. The properties of the medium do. You can FIND the speed by measuring the wave's frequency and wavelength.