1. All things considered, which shopping bag do you think is best: plastic, paper, or reusable cloth bags? Defend your answer. Canadians use 55 million plastic bags each week.

Concerns about plastic bags have motivated retailers to take action. Consider the following examples:

• Cities as different as San Francisco, California, and Leaf Rapids, Manitoba, have banned the use of plastic bags; several grocers in Nova Scotia are also considering the move.

• Walmart and many other retailers are training their cashiers to ask customers if they even need a bag of any kind.

• Loblaws has sold more than 14 million reusable bags, and the number of plastic bags given to customers has been reduced by 20 percent.

• Many stores, including IKEA and No Frills charge customers for plastic bags and try to encourage consumers to use reusable bags.

• Mountain Equipment Co-op wants to convince customers to stop using disposable bags altogether, so it makes a five-cent donation to environmental groups each time a customer declines to take a plastic bag.