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What node is return by before$($J$)?$ In other words, what is the predecessor of

J$?$ What node is return by before$($E$)?$ In other words, what is the predecessor of

$E?$

What node is return by before$(N?$ In other words, what is the predecessor

of $N?$

What node is return by before$($C$)?$ In other words, what is the predecessor of

C$?$

What node is return by before$($D$)?$ In other words, what is the predecessor

of D$?$