Human activities can have positive and negative effects on the environment Humans can benefit natural areas by CA throwing waste products in these areas. B. removing all the vegetation from these areas. c. polluting the areas by burning fossil fuels. D. preserving the natural resources that they provide

Iron reacts with sulfur to form iron sulfide. if 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?