Given, time between transmission and detection, t = 1.71 s
Speed of ultrasound through sea water, v = 1531 m/s
Distance travelled by the ultrasound = 2 x Depth of the sea = 2d
2d = vxt = 1531 x 1.71 = 2618.01 m
d = 2618.01 / 2 = 1309 m
Hence, the distance of the sea bed from the ship is 1309 m.