In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: what is the minimum number of square tiles required to tile a floor of length 5 metres 78 cm and width 3 metres 74 cm ? 
Options: a ) 187 , b ) 180 , c ) 190 , d ) 195 , e ) 197

Ex Output:
a


Ex Input:
Problem: calculate the speed of a boat in still water ( in km / hr ) if in one hour , the boat goes 10 km / hr downstream and 4 km / hr upstream . 
Options: a ) 7 kmph , b ) 8 kmph , c ) 9 kmph , d ) 7 kmph , e ) 6 kmph

Ex Output:
a


Ex Input:
Problem: two trains of equal lengths take 10 sec and 15 sec , respectively , to cross a telegraph post . if the length of each train is 120 m , in what time will they cross each other , travelling in opposite directions ? 
Options: a ) 17 sec , b ) 12 sec , c ) 18 sec , d ) 19 sec , e ) 52 sec

Ex Output:

b