Apply the backflow algorithm to the digraph below

T$1(4)$

T$2(2)$

T$3(8)$

T$4(7)$

T$5(10)$

T$6(11)$

T$7(12)$

T$8(6)$

T$9(9)$

T$10(3)$

End

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Task $5$ has a critical time of

Task $2$ has a critical time of