Final answer:
To evaluate the expression (7y^3/5 * 6x+5/21y), you first simplify the expression inside the parentheses. Then, you multiply the numerator and denominator of the fraction by 7 to eliminate the fraction. Finally, you cancel out the y terms and simplify the expression to get the correct answer.
Step-by-step explanation:
To evaluate the expression (7y^3/5 * 6x+5/21y), we can simplify it step by step.
First, simplify the expression inside the parentheses.
6x+5/21y can be written as (6x+5)/(21y).
Then, multiply the numerator and denominator of the fraction by 7 to eliminate the fraction. We get:
(7y^3/5) * (7(6x+5)/(21y)) = (49y^3(6x+5))/(35*21y).
Cancel out the y terms:
(49y^2(6x+5))/(35*21) = (6x+5)/(15).
So the correct answer is $(c) (2(6x+5)/15)$.