Compare and contrast CD and DVD?

Robots with telescoping arms are sometimes used to perform tasks (e.g., welding or placing screws) where access may be difficult for other robotic types. during a test run, a robot arm is programmed to extend according to the relationship r = 3 + 0.5cos(4θ) and the arm rotates according to the relationship θ=−π4t2+πt , where r is in feet, θ is in radians, and t is in seconds. use a computer program to plot the path of tip a in x and y coordinates for 0 ≤ t ≤ 4s.

Technician a says that with self-adjusting clutch systems, the release bearing constantly rotates. technician b says that the ball bearing portion of the release bearing should be lubricated with high-temperature grease during routine maintenance. which technician is correct?

What is the total resistance in a circuit that contains three 60 ohm resistors connected in a series? a. 20 ohms b. 120 ohms c. 60 ohms d. 180 ohms