(i) Express \(5x^2-14x-3\) in the form \(p(x+q)^2+r\), where \(p\), \(q\) and \(r\) are constants.

(ii) Sketch the graph of \(y=\left|5x^2-14x-3\right|\). Show clearly any points where your graph meets the coordinate axes.

(iii) State the set of values of \(k\) for which \(\left|5x^2-14x-3\right|=k\) has exactly four solutions.