[单选题]
One 20-year-old twin brother tgnlj*qvt(s, ,c r)r0makes a space trip with1-u/dp j 0,fjbve30wy arjd:b a speed of 0.80c for 30 years according to a clock on the spacesd ea3d,j1r bf 0uj j-:y0wvbp/hip. Upon returning to the Earth, what is his own age and the age of the Earth-based twin brother?
Post time 2024-1-14 16:03:04