✓ Why were firearms a crucial element in the creation of new trade empires? Give 2
examples.

Apipe with an outside diameter of 15 cm is exposed to an ambient air and surrounding temperature of -20°c. the pipe has an outer surface temperature of 65°c and an emissivity of 0.85. if the rate of heat loss from the pipe surface is 0.95 kw per meter of length, the external convective heat transfer coefficient (h) is: (a) 12.5 w/m"k (b) 18.6 w/mk (c) 23.7 w/mk (d) 27.9 w/mk (e) 33.5 w/mk

Which of the following ziegler nichols tuning methods the response of the controller to a step input should exhibit an s-shaped curve? a)-open loop mode b)-closed loop mode c)-both modes (open & closed) d)-none of the modes (open & closed)

Select any two (2) areas of applications of chain-drive. (clo4) a)-permanent lubrication necessary b)-hydraulic forklift truck operation c)-rigging and heavy moving materials d)-relatively high maintenance costs e)-costlier than belt drives