need answers of b and c

20.50 For each of the following, identify the product (represented by A,B, and C ) that would be formed through the indicated sequence of steps from the given starting material. (1) NaN3 (excess) (2) (a) LDA (1 equiv), (b) (1) NaOMe,MeOH (2) H2O (3) (a) HNMe2,HA (cat.) (3) H3OA (b) (4) LiAlH4 (excess) (5) H3O (b) NaCNBH3 (4) H3O+,A (5) DCC, NH3 (6) Br2,NaOH,H2O (7) H2O (c) (1) H2CO, (2) H2NNH2,HA ( C (2) H2NNH2, HA (3) KOH1