Two connected right triangles

Points \(B,K,C\) are collinear. Segments \(AB\) and \(HK\) are perpendicular to \(BC\), while \(A,H,C\) are collinear. Given \(BK=8\) cm, \(KC=15\) cm and \(HK=10\) cm, find

1. \(\angle ACB\),
2. \(AB\). Give non-exact lengths, areas and other numerical values to 3 significant figures, and angles to 1 decimal place, unless otherwise stated.