[填空题]
A light-year is the distance lig no(2/jkf0 . (qaczexd tkp1q7efpypwxr8d-9m 27wv zj; rd *0ht travels in one year (at speed = $2.998 \times 10^8 \; m$). (a) How many meters are there in 1.00 light-year? $\times 10^{15}$ (b) An astronomical unit (AU) is the average distance from the Sun to Earth, $1.50 \times 10^8 \; km$. How many AU are there in 1.00 light-year? $\times 10^{4}$