"Must the Price Be Put on Goods and Services Provided by World's Ecosystems". Read pro and con arguments, do your own study on web, and then present completely supported (by cited sources in and at the end of your essay) opinion on topic in a well developed essay. You will have to 'sift through' quite bit of rhetoric on the subject and come to scientific, informed opinion to get full credit for post. Embed images and videos as suitable to enhance your positions. You will require at least 3 sources, may be more, beyond the required readings to really flesh out your position.