Answer:
398.22 kg
Step-by-step explanation:
mass of I canoe, m1 = 320 kg
initial velocity of both the canoe = 0
final velocity of I canoe, v1 = 0.56 m/s
final velocity of II canoe, v2 = - 0.45 m/s
Let the mass of second canoe is m2.
Use conservation of momentum
momentum before push = momentum after push
0 + 0 = m1 x v1 + m2 x v2
0 = 320 x 0.56 - m2 x 0.45
m2 = 398.22 kg
Thus, the mass of second canoe is 398.22 kg.