The time between the calls at a telephone switch is an exponential rv t with an expected value of e[t]=0.02. given that t > 0.03 a. what is e[t |t> 0.03 ], the conditional expected value of t ? b. what is variance var[t |t> 0.03] and the conditional variance of t ?

Water at the rate of 1 kg/s is forced through a tube with a 2.5 cm inner diameter. the inlet water temperature is 15°c, and the outlet water temperature is 50°c. the tube wall temperature is 14°c higher than the local water temperature all along the length of the tube. what is the length of the tube?

Apressure vessel with an r/t 20 cannot be treated as thin walled vessel. a)-trune b)- false

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