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: for what values of k will the pair of equations 4 ( 3 x + 4 y ) = 48 and kx + 12 y = 30 does not have a unique solution ? 
Options: a ) 12 , b ) 9 , c ) 3 , d ) 7.5 , e ) 2.5
b

Problem: when the price of sugar was increased by 32 % , a family reduced its consumption in such a way that the expenditure on sugar was only 10 % more than before . if 30 kg were consumed per month before , find the new monthly consumption . 
Options: a ) 20 kg , b ) 25 kg , c ) 30 kg , d ) 35 kg , e ) none of these
b

Problem: if x + ( 1 / x ) = 5 , what is the value of t = x ^ 2 + ( 1 / x ) ^ 2 ? 
Options: a ) t = 21 , b ) t = 22 , c ) t = 23 , d ) 24 , e ) 27

c