A mower has drive wheel of 60 cm diameter. The crank of the mower makes 600 rev/min when it is driven by a tractor, moving at a speed of 2.3 km/hr. If the speed ratio between the crank wheel and land wheel is changed to 27:1, calculate the increase in speed of mower to maintain same speed of crank.

• A. 0.19 km/hr
• B. 0.67 km/hr
• C. 0.11 km/hr
• D. 0.21 km/hr