If the motor axial specific impulse of a given nozzle is 340s for propellant A and its characteristic velocity is 1400 m/s, determine the specific impulse for the same nozzle using a propellant B with a characteristic velocity of 980 m/s. Assume both propellants A and B have the same specific heat ratio.

• A. 259 s
• B. 286 s
• C. 277 s
• D. 238 s