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: company x provides bottled water to its employees in 5 liter bottles , $ 2 each . at least how many 5 l bottles must company x buy monthly , so that new contract with $ 100 fixed monthly rate and $ 1 for 10 l bottle each paid off ? ( assume that no other costs apply )
Options: a ) 121 , b ) 125 , c ) 132 , d ) 134 , e ) 138
d

Problem: the sum of the first 50 positive even integers is 2550 . what is the sum w of even integers from 102 to 200 inclusive ?
Options: a ) 5100 , b ) 7550 , c ) 10100 , d ) 15500 , e ) 20100
b

Problem: a man whose speed is 6.5 kmph in still water rows to a certain upstream point and back to the starting point in a river which flows at 1.5 kmph , find his average speed for the total journey ?
Options: a ) 5.33 kmph , b ) 6.00 kmph , c ) 5.00 kmph , d ) 6.00 kmph , e ) 4.00 kmph
a