Write three helper functions for a candy shop that sells three different types of sweets: saltwater taffy, fudge, and praline. They sell the saltwater taffy for $5.99 / lb. They sell the fudge for $9.99 / lb. They sell the praline for $8.99 / lb. Write a helper function for each type of sweet that takes the weight of the candy sold and returns the cost for the candy type. Round each to 2 decimal places.