In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: a car dealership has 40 cars on the lot , 30 % of which are silver . if the dealership receives a new shipment of 80 cars , 40 % of which are not silver , what percentage of total number of cars are silver ? 
Options: a ) 35 % , b ) 37.5 % , c ) 45 % , d ) 47.5 % , e ) 50 %
e

Problem: the area of a circle is increased by 1500 % . by what percent has the radius of the circle increased ? 
Options: a ) 100 % , b ) 200 % , c ) 300 % , d ) 600 % , e ) 800 %
c

Problem: ajay bought 15 kg of dal at the rate of rs 14.50 per kg and 10 kg at the rate of rs 13 per kg . he mixed the two and sold the mixture at the rate of rs 15 per kg . what was his total gain in this transaction ? 
Options: a ) rs 1.10 , b ) rs 11 , c ) rs 16.50 , d ) rs 27.50 , e ) none of these

d