3. Given
\(\cos \theta ^ { \circ } = p\), where \(p\) is a constant and \(\theta ^ { \circ }\) is acute use standard trigonometric identities to find, in terms of \(p\),
- \(\sec \theta ^ { \circ }\)
- \(\sin ( \theta - 90 ) ^ { \circ }\)
- \(\sin 2 \theta ^ { \circ }\)
Write each answer in its simplest form.