Table:
text: Rail transportation in Solano County, California
Population of Solano County Towns
Population of Solano County Towns
City _1860 _1870 _1880 _1890 _1900 _1910 _1920
Benicia 1470 1656 2067 2951 2751 2360 2693
Dixon N/A N/A N/A 1082 783 827 926
Elmira N/A N/A 816 869 717 494 452
Rio Vista N/A 888 1232 1236 682 884 1104
Vacaville 1831 1701 1299 2712 1220 1177 1254
Vallejo 1431 6391 6587 6866 7965 11340 21107

Question: What is the number for 1880 for rail travel in Solano County, California when 1860 is N/A and 1910 is 494?

Question: What is the 1920 number if 1890 is greater than 1,236, 1910 is less than 1,177, and the city of Vacaville is among the rail transit modes in Solano County, California?