The online company sells handmade samurai katana swords. Website costs $ 160 a month to maintain. Every katana costs $ 290 to make, and they sell every katana for $ 680.
i) Create the linear model in form y = m x + b where x is number of swords sold per month and y is net monthly profit.
ii) Using the model, determine number of swords which would require to be sold per month to have the monthly profit of $ 4780.