2. A sign that has a white background with a green panel with white lettering is a
a. general information sign
b. safety instruction sign
c. caution sign
d. danger sign

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.

Brief discuss how the presence of dislocations in crystal structures can be an advantage and a disadvantage to engineer and designers.

List 3 options on how to reduce knocking problens during engine process,