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

Problem: the manager at a health foods store mixes a unique superfruit juice cocktail that costs $ 1399.45 per litre to make . the cocktail includes mixed fruit juice and a ç ai berry juice , which cost $ 262.85 per litre and $ 3104.35 per litre , respectively . the manager has already opened 33 litres of the mixed fruit juice . how many litres of the a ç ai berry juice does he need to add ? 
Options: a ) 17 litres , b ) 22 litres , c ) 11 litres , d ) 07 litres , e ) 38 litres
b

Problem: two trains of equal length are running on parallel lines in the same directions at 46 km / hr . and 36 km / hr . the faster trains pass the slower train in 144 seconds . the length of each train is : 
Options: a ) 82 m , b ) 150 m , c ) 172 m , d ) 200 m , e ) none of these
d

Problem: the smallest value of n , for which 2 n + 1 is not a prime number is 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

b