Suppose Lori has an income of $100 to spend on chocolate bars and ice-cream cones.  She faces a price of $1 for chocolate bars.  However, the price of ice-cream depends on how much you buy.  The first 10 icecream cones cost Lori $2 each, but each cone after that is $0.50 each.  Draw the budget constraint where chocolate bars are on the vertical axis and ice-cream cones are on the horizontal axis.  Clearly indicate at what quantities will there be a kink in the budget constraint.