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Suppose that a comet that was seen in 563 a. d. by chinese astronomers was spotted again in year 1951. assume the time between observations is the period of the comet and take its eccentricity as 0.986. what are (a) the semimajor axis of the comet's orbit and (b) its greatest distance from the sun?

Order the sequence of ideas that lead to marie curies discovery of radioactive elements number the events in chronological order starting with the oldest

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.