A new drug has been released to the public and is popular among consumers. It is effective in relieving high blood pressure. However, it has
altered some patients' personalities. Which stage of the engineering process
may address this negative side effect?
A. Screening
B. Testing
C. Looking for improvements
D. Evaluating test results

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.