Which products result in a difference of squares or a perfect square trinomial

Idrk but i think u should figure out the n dia n then the units it will make it way more easier

The answer would be a

So don't take my word i'm not exactly a mathematical person but i would assume a. because while selling the soap every month you increase in sells so you would by 11 percent. the you would get the factor 0.89 which if i had to guess would be the monthly profit over 11 probably wrong tho