The southeast and canadian shield area of quebec are centers of what?

Forestry and mining, Having been to Canada four times (I'm a U.S. citizen), the main agricultural area of Eastern Canada is in the peninsula region of Ontario between Lake Erie and Lake Ontario to the south.and Lake Huron on the morthwestern arm of the peninsula. There is als0 an agricultural region along the southern portion of the land between the U.S. and the Saint Lawrence River Once you get out of the Saint Lawrence River Valley, you hit an immense forested area that spans all the way across Eastern Canada (even into Western Canada).that covers hundreds of thousands of square miles (or square kilometers). Since there are trees in this region (known as the Canadian Shield), the forestry industry seems fairly obvious. What isn't so obvious is that this region is full of deposits of iron ore, nickel, copper, gold, and several other metals commonly mined.

Sonar is an application of the doppler effect used by submarines.  this test was on k12.