Dr. Aloysius found four homogeneous mixtures, but he thinks that only three are alloys. He tests each one and determines their elemental compositions. Which of the following is not a possible alloy?

The bar of prob. 5/82 is repeated here. the ends of the 0.4-m bar remain in contact with their re- spective support surfaces. end b has a velocity of 0.5 m/s and an acceleration of 0.3 m/s2 in the di- rections shown. determine the angular accelera- tion of the bar and the acceleration of end a.