Consider the completed table below, which calculates the shortest distance to all nodes from U:

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$|$ Node $|$ Shortest distance from U $|$ Previous Node $|$

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U $0$ n$/$a

W $3$ U

X $4$ U

Y $4$ W

Z $6$ Y

V $7$ U

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Question $1$ of $2$

For link X$,$ what is the cost associated with this link? If the answer can't be determined given the information, respond with $\text{'}$n$/$a$\text{'}$