In this task, you need to provide the correct option for a given problem from the provided options.

Problem: assisants are needed to prepare for preparation . each helper can make either 2 large cakes or 35 small cakes / hour . the kitchen is available for 3 hours and 20 large cakes and 700 small cakes are needed . how many helpers are required ?
Options: a ) 9 , b ) 10 , c ) 13 , d ) 16 , e ) 18
b