High above the surface of the earth, charged particles (such as electrons and protons) can become trapped in the earth's magnetic field in regions known as van allen belts. a typical electron in a van allen belt has an energy of 40 kev and travels in a roughly circular orbit with an average radius of 210 m. what is the magnitude of the earth's magnetic field where such an electron orbits?

The double bond between a carbon atom and two oxygen atoms (a molecule of carbon dioxide) has two characteristics. what are they? a.an ionic bond is formed between the oxygen and carbon atoms. b.four valence electrons are shared. c.two valence electrons are shared. d.valence electrons are shared between oxygen atoms.

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.

The wind is to parities grasses because it them