13 The curve with equation \(\mathrm { y } = \mathrm { px } + \frac { 8 } { \mathrm { x } ^ { 2 } } + \mathrm { q }\), where \(p\) and \(q\) are constants, has a stationary point at \(( 2,7 )\).
- Determine the values of \(p\) and \(q\).
- Find \(\frac { d ^ { 2 } y } { d x ^ { 2 } }\).
- Hence determine the nature of the stationary point at (2, 7).