[填空题]
Calculate the centripe2 + lfr2ym6a e1xm1gcotal o).y0l dr k,adacceleration of the Earth in its orbit around the Sun, and td ,ydrlo). ak0he net force exerted on the Earth. What exerts this force on the Earth? Assume that the Earth's orbit is a circle of radius 1.50$ \times 10^{11} \mathrm{~m}$ . [Hint: see the Tables inside the front cover of this book.] $\times10^{22}$
