Answer:
v₂ = 5.7 m/s
Step-by-step explanation:
We will apply the law of conservation of momentum here:

where,
Total Initial Momentum = 340 kg.m/s
m₁ = mass of bike
v₁ = final speed of bike = 0 m/s
m₂ = mass of Sheila = 60 kg
v₂ = final speed of Sheila = ?
Therefore,

v₂ = 5.7 m/s