Name the types of following triangles:

(a) Triangle with lengths of sides 7 cm, 8 cm and 9 cm.

(b) ΔABC with AB = 8.7 cm, AC = 7 cm and BC = 6 cm.

(c) ΔPQR such that PQ = QR = PR = 5 cm.

(d) ΔDEF with m∠D = 90°

(e) ΔXYZ with m∠Y = 90° and XY = YZ.

(f) ΔLMN with m∠L = 30°, m∠M = 70° and m∠N = 80°