Task: Question Answering
Input (English): Problem: a trader mixes 80 kg of tea at 15 per kg with 20 kg of tea at cost price of 20 per kg . in order to earn a profit of 35 % , what should be the sale price of the mixed tea ? 
Options: a ) 23.75 , b ) 21.6 , c ) 20 , d ) 19.2 , e ) none of these
Output (English): b