Answer: The speed of the airliner is approximately 258.2 m/s.
Explanation: We can use the formula for kinetic energy:
K.E. = 1/2mv^2
where K.E. is the kinetic energy, m is the mass, and v is the velocity (speed).
Rearranging the formula to solve for v, we get:
v = sqrt(2K.E./m)
Substituting the given values, we get:
v = sqrt(2(2x10^9 J)/(6x10^4 kg))
v = sqrt(66666.67 m^2/s^2)
v ≈ 258.2 m/s