What would be the percentage changes in net margin if Doggie Treats were to consider marketing inputs as follows:

a$)$ Reduce research and development $10\%?$

b$)$ Reduce marketing and advertising $10\%?$

c$)$ Reduce all fixed costs $10\%?$

d$)$ Reduce all variable costs $10\%?$

a$)$ Reduce research and development $10\%?$

b$)$ Reduce marketing and advertising $10\%?$

c$)$ Reduce all fixed costs $10\%?$

d$)$ Reduce all variable costs $10\%?$