What evidence did ottawa scientists collect in researching pcb concentrations in alaska?

The correct answer is PCBs were found in greater concentrations in lakes where more salmon spawned. It also worked vice versa as smaller amounts of PCBs were found in lakes where fewer salmon spawned. This led to great polemics on safety and on how it should be reduced.

The correct answer is - A) Many crops would die because the irrigation water will be limited.

The Ogallala aquifer is essential for the farming of plants. For decades it has been used without taking in consideration the long terms of its emptying. Lots of farmers were increasing in size the farmlands they had to manage to have bigger profits. Very often the plants planted were plants not needed for the home market and also very demanding of water, like almonds for example. Since it became obvious that the water for irrigation is coming to an end lots of the farmlands have been abandoned and plantations destroyed, and this process will continue until there's no more water left in the aquifer.