Decades: 1990s 2000s 2010s 2020s 2030s - 2040s - 2050s 2060s 2070s 2080s 2090s
Years: 2040 2041 2042 2043 2044 2045[?] 2046 2047 2048[?] 2049[?]
... in some other set. That is, given classes A and B, A is a subclass of B if and only if every member of A is also a member of B. If A and B are sets, then of ...