Nikita bought 30 kg of wheat at the rate of Rs. 9.50 per kg and 40 kg of wheat at the rate of Rs. 8.50 per kg and mixed them. She sold the mixture at the rate of Rs. 8.90 per kg. Her total profit or loss in the transaction was `R s .2\ los s` b. `R s .2\ p rofi t` c. `R s .7\ los s` d. Rs. 7 profit