If a new bridge to Canada is built:

Provide and explain an example of a negative externality.

Provide and explain an example of a positive externality.

If a new bridge is built to Canada an example of a negative externality could be that the production of the bridge harms the river below the bridge. Another example of a negative externality could be that the new bridge increases traffic in the area which increases pollution and harms the surrounding environment. A positive externality could be that the increased traffic in the area from the construction of the bridge supports the local economy and the businesses nearby.