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 unit digit in the product ( 784 x 618 x 917 x 463 ) is :
Options: a ) 5 , b ) 9 , c ) 16 , d ) 2 , e ) 42
d

Problem: the largest 5 digit number exactly divisible by 91 is :
Options: a ) 25698 , b ) 581396 , c ) 369741 , d ) 99918 , e ) 1258
d

Problem: java house charges $ 4.25 for a cup of coffee that costs a total of $ 3.85 to make . cup ' o ' joe charges $ 4.80 for a cup that costs $ 4.65 to make . if java house sells 55000 cups of coffee , how many must cup ' o ' joe sell to make at least as much in total gross profit as its competitor does ?
Options: a ) 7,858 , b ) 8,301 , c ) 14,667 , d ) 63,840 , e ) 146,667
e