2
Exercise:
1. The cost of an apple has decreased from $0.50 to $0.40. Work out the decrease cost of an
apple as a percentage.

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