T1:  R(A)        W(C)                                W(D)
T2:        R(B)                          W(C)
T3:                    R(D)        W(B)
T4:                          R(E)              W(A)

Assume that: each R acquires a shared lock; each W uses an exclusive lock; two-phase locking is used.

Show how the wait-for graph for the locks evolves.

Show how any deadlocks might be resolved via this graph.