The motor pulls on the cable at A with a force where t is in seconds. If the 34-lb crat...

The motor pulls on the cable at A with a force where t is in seconds. If the 34-lb crate is originally at rest on the ground when t = 0, determine its speed when t = 4 s. Neglect the mass of the cable and pulleys. Hint First find the time needed to begin lifting the crate.