Which type of triangle is this triangle with length of sides 7 cm 8 cm and 9 cm? (a) Triangle with lengths of sides 7 cm, 8 cm and 9cm. (b) ABC with AB = 8.7 cm, AC = 7 cm and BC = 6cm. (c) PQR such that PQ = QR = PR = 5cm. (d) DEF with D = 90 degrees (e) XYZ with Y = 90 and XY = YZ (f) LMN with L = 30, M = 70 and N = 80.