Abrown dwarf is o another name for a main-sequence star. a star of less than about 1½ solar masses at the very end of its life, after it has cooled to near-invisibility o any star whose black-body spectrum peaks in the brown region of the visible spectrum o an object intermediate between a planet and a star, with not enough mass to begin nuclear reactions in its core.

At which point on the diagram do convection currents occur to drive plate movement?

Ozone in the upper atmosphere has been depleted by a. sulfur dioxide. b. chlorofluorocarbons. c. carbon dioxide. d. oxygen.

If we review the changes in the landscape surrounding the great salt lake in utah we can see a change in topography. look at the area to the south of the lake. what change has occurred during the last twenty-nine years? a) erosion of the hills b) an increase in marshland c) flooding of the area and the development of wetlands d) deposition of sediments and an increase in elevation