Earth's ice sheets grow and retreat on a cycle of about 41,000 years. Which natural process is responsible for this cycle?
A. the eccentricity of Earth's orbit
B. the wobble in Earth's tilt on its axis
C. the El Nino Southern Oscillation
D. the changing size of the Ozone hole

When the ionic compound nabr dissolves in water, br– ions are pulled into solution by the attraction between what two particles? a. the na+ and br– ions b. the na+ ion and the negative end of a water molecule c. the br– ion and the positive end of a water molecule d. the br– ion and the negative end of a water molecule