Rates Jokes

Why do chemists like nitrates so much?
They're cheaper than day rates.
Did you know that you can get a slice of lemon pie in Cuba for $1.50, but in Jamaica you can get key lime pie for $1.00?
Those are the pie rates of the Carribean.
Cherry pie will set you back 10 dollars in Antigua, but 15 in Barbados. Yes, those are the pie rates of the Caribbean.