Write the following as a single sine or cosine function of an angle: \( \cos ^{4} 3 x-\sin ^{4} 3 x \)

In \( \triangle \mathrm{GHI}, g=9.6 \) inches, \( m \angle \mathrm{I}=80^{\circ} \) and \( m \angle \mathrm{G}=15^{\circ} \). Find the length of \( h \), to the nearest 10th of an inch.

In \( \triangle \mathrm{PQR}, p=4.7 \) inches, \( m \angle \mathrm{P}=76^{\circ} \) and \( m \angle \mathrm{Q}=57^{\circ} \). Find the length of \( q \), to the nearest 10th of an inch.

In \( \triangle \mathrm{TUV}, u=750 \mathrm{~cm}, m \angle \mathrm{~T}=105^{\circ} \) and \( m \angle \mathrm{U}=42^{\circ} \). Find the length of \( t \), to the nearest centimeter.

In \( \triangle \mathrm{GHI}, g=9.6 \) inches, \( m \angle \mathrm{I}=80^{\circ} \) and \( m \angle \mathrm{G}=15^{\circ} \). Find the length of \( h \), to the nearest 10th of an inch.

In \( \triangle \mathrm{IJK}, k=1.9 \) inches, \( m \angle \mathrm{~J}=59^{\circ} \) and \( m \angle \mathrm{~K}=18^{\circ} \). Find the length of \( j \), to the nearest 10 th of an inch.