CThe wave will reflect back into air
c
Since $\mathrm{V}_{\text {liquid }}>\mathrm{V}_{\text {Air }}$
i.e. liquid is rarer than air for sound waves
Angle of total internal reflection (critical angle)
$=\sin ^{-1}\left(\frac{\mathrm{v}_{\mathrm{liq}}}{\mathrm{v}_{\mathrm{air}}}\right)=\sin ^{-1}\left(\frac{1}{2}\right)=30^{\circ}$
Hence sound wave is totally reflected back.