A CNF for F = {w {a, b} | w is a palindrome } is given by the rules:

S | AA | BB | a | b | AT,

U AT | BW | AA | BB | a | b,

T UA,

W UB,

A a,

B b,

where S is the start variable. Suppose M is a PDA that accepts F by simulating the leftmost derivation according to the grammar. Show a path for M to accept abababa. Explain your work.