प्रकाश एका वर्षात ______ किमी प्रवास करू शकतो. A. 5 बिलियन B. 10 बिलियन C. 5 ट्रिलियन D. 10 ट्रिलियन

Light travels about 3 × 10⁵ km/s, and a year has about 3.15 × 10⁷ seconds, so in a year light covers about 9.46 × 10¹² km. This distance, one light-year, is roughly 10 trillion km.