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: a cyclist rides a bicycle 7 km at an average speed of 10 km / hr and again travels 10 km at an average speed of 7 km / hr . what is the average speed for the entire trip ? 
Options: a ) 7.59 , b ) 7.79 , c ) 7.99 , d ) 8.19 , e ) 8.39
c

Problem: tara bought 19 cartons of ice cream and 4 cartons of yoghurt . each carton of ice cream cost $ 7 and each carton of yoghurt cost $ 1 . how much more did tara spend on ice cream than on yoghurt ? 
Options: a ) $ 144 , b ) $ 130 , c ) $ 80 , d ) $ 110 , e ) $ 129
e

Problem: a certain class of students is being divided into teams . the class can either be divided into 16 teams with an equal number of players on each team or 24 teams with an equal number of players on each team . what is the lowest possible number of students in the class ? 
Options: a ) 6 , b ) 36 , c ) 48 , d ) 60 , e ) 72

c