Only solve question 5 please

Problem 3 and 4 is below. You can use this info to solve problem 5.

5. Use the results from Problem 3 and 4 to show that, if JA = -C DABDXA) then ja = -p DABDWA where the binary diffusivity DAB is the same in both cases. Here, XA is the mole fraction of A in a binary mixture of A and B. 3. For a binary mixture of components A and B, it must be true that ja + js = JAMWA + JMW, = 0, where MW; is the molecular weight of i. Use this result to show that MW:C JA JA where C is the total molar concentration and p is the density of the mixture. 4. Show that, in a binary mixture, the gradient of the mass fraction wa is related to the gradient in the mole fraction xa by MWAMW (xqMWA + XpMW3)2 V = TXA