Treat the basic description and dynamics of satellite orbits Major perturbations on GPS satellite orbits · Sources of orbit information: -SP3 format from the International GPS service Broadcast ephemeris message
National Income: Where t comes From and where丨 t Goes A large income is the best recipe for happiness I ever heard of. Jane Austen The most important macroeconomic variable is gross domestic product(GDP) As we have seen, GDP measures both a nations total output of goods and ser- vices and its total income. To appreciate the significance of GDP, one need only take a quick look at international data: compared with their poorer counterparts, nations with a high level of gDP per person have everything from better child-
