1- (50 points) Consider the following soil profile. If a fill with unit weight of 120 lbf/ft3 and height of 10 ft is planned to be placed on the field, estimate: a) The primary consolidation settlement if the preconsolidation stress is 1100 psf. b) The degree of consolidation and the corresponding settlement six months after loading. c) The time (in minutes) that it takes for a 1-in-thick lab specimen of this soil to get to the same degree of consolidation as the field. d) The secondary and total consolidation 6 years after placement of the fill if the time to complete primary consolidation is 1.6 years.

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

The drive force for diffusion is 7 fick's first law can be used to solve the non-steady state diffusion. a)-true b)-false

Which of the following components of a pid controlled accumulates the error over time and responds to system error after the error has been accumulated? a)- proportional b)- derivative c)- integral d)- on/off.