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: 10 is added to a certain number , the sum is multiplied by 2 , the product is divided by 2 and 2 is subtracted from the quotient . the remainder left is half of 88 . what is the number ? 
Options: a ) 21 , b ) 20 , c ) 25 , d ) 36 , e ) 45
d

Problem: whats the reminder when 879,548 , 521,456 , 258,759 , 653,258 , 778,455 , 658,985 is divided by 4 
Options: a ) 1 , b ) 7 . , c ) 2 . , d ) 3 , e ) 9
a

Problem: the cost of 10 kg of mangos is equal to the cost of 24 kg of rice . the cost of 6 kg of flour equals the cost of 2 kg of rice . the cost of each kg of flour is $ 21 . find the total cost of 4 kg of mangos , 3 kg of rice and 5 kg of flour ? 
Options: a ) 347.8 , b ) 987.8 , c ) 877.8 , d ) 898.8 , e ) 667.4

d