Determine the batch quantities for a concrete mix design to have a 28-day compressive strength of 4000 psi, using sub-angular aggregate .The fine aggregate has a fineness modulus of 2.5. The concrete is used in severe weather, however we will use non-air entrained. A slump of 3 in is desired. Use a 350 psi standard deviations of compressive strength of concrete (more than 30 samples).

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.

Most leaks in reciprocating air compressors can be detected and minimized by: (clo4) a)-detecting leakage areas using ultrasonic acoustic detector. b)-tightening joints and connections c)-replacing faulty equipment d)-all of the given options

A)-in the process of engineering design, explain the contribution of material selection. b)- explain the procedure of synthesis as is employed in engineering design. c)- is there any relationship between ergonomics and engineering design? explain. d)- safety consideration in engineering design includes human, product and the enviroment . explain how safety will be incorporated into the design?