<span>The Appalachian Mountains were formed when colliding tectonic plates folded and upthrust, mainly during the Permian Period and again in the Cretaceous Period. The folds and thrusts were then eroded and carved by wind, streams and glaciers. These erosive processes are ongoing, and the topography of the Appalachian Mountains continue to change. They have changed with the miles of land that are cleared of all vegetation and topsoil. In the 1970's coal miners literally blow away the top of a mountain to get to the coal underneath.</span>

= (18 x 10^-6 /°C)(0.125 m)(100° C - 200 °C)
= -0.00225 m
New length = L + ΔL
= 1.25 m + (-0.00225 m)
= 1.248
D
Are there supposed to be multiple choices for this question?
Answer:
Explanation:
The velocity of the wrench must be equal to the velocity of the truck . So momentum of the wrench before it hits the wall
= mv = 6 x 13.3 = 79.8 kg m /s
If resisting force of wall be F , impulse on the wrench = F x time
= F x .07
Impulse = change in momentum of the wrench = mv - 0 = mv = 79.8 kgm/s
So F x .07 = 79.8
F = 1140 N .