Which of these statements is the best reason for countries to work together to address environmental issues? a. international treaties are largely ineffective because developing countries lack the resources to enforce them. b. pollution made in one country might contaminate the ground, water, and air of other countries c. pollution made in one country trends to stay in that country and harm only that country's residents d. environmental damage is caused mainly by developing countries that need to work together.

It may seem strange that the selected velocity does not depend on either the mass or the charge of the particle. (for example, would the velocity of a neutral particle be selected by passage through this device? ) the explanation of this is that the mass and the charge control the resolution of the device--particles with the wrong velocity will be accelerated away from the straight line and will not pass through the exit slit. if the acceleration depends strongly on the velocity, then particles with just slightly wrong velocities will feel a substantial transverse acceleration and will not exit the selector. because the acc