Solve the Problem $30 \mathrm {~m}$ And It Is $18 \mathrm {~m}$

Multiple Choice

Solve the problem.
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A tunnel is in the shape of a parabola. The maximum height is $30 \mathrm {~m}$ and it is $18 \mathrm {~m}$ wide at the base. What is the vertical clearance $2 \mathrm {~m}$ from the edge of the tunnel?

A) $11.9 \mathrm {~m}$
B) $28.5 \mathrm {~m}$
C) $18.1 \mathrm {~m}$
D) $1.5 \mathrm {~m}$