a The reaction A - B is carried out in a laboratory reactor. The concentration CA is a function of time according to the formula: CA = CAO expc-kt) where Cao is the initial concentration of A in the reactor and k is a constant. (a) Find CA and k (b) Calculate CA at at 1 = 240 s (min) 0.5 1.0 1.5 2.0 CA (lb-mole/tt) 1.02 0.84 0.69 0.56 0.38 0.17 0.02 3.0 5.0 10.0