What is the relationship between time and transportation infrastructure? (Select all that apply.) Replacement of parts of the transportation infrastructure could take decades. Many unscheduled delays result from interruptions in service. The time for replacing the existing infrastructure has already passed. Much of the existing transportation infrastructure is very old.

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

What precautions should you take to prevent injuries when dealing with heavy loads?

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.