`a, 110+ 126: 2,8xx 6,4 `
` = 110 + 45 xx 6,4 `
` = 110 + 288`
` = 398`
`b,19/7xx9/13-9/13xx 5/7`
` = 9/13 . (19/7 - 5/7)`
` = 9/13 . 2`
`= 18/13`
` c,(2011/ 2012+ 2012/ 2013+ 2013/ 2014) xx(1+1xx 2 +1xx2xx3-9)`
` = (2011/ 2012+ 2012/ 2013+ 2013/ 2014) xx ( 1 + 2 + 6 - 9)`
` = (2011/ 2012+ 2012/ 2013+ 2013/ 2014) xx ( 3 +6 -9)`
` = (2011/ 2012+ 2012/ 2013+ 2013/ 2014) xx (9-9)`
` = (2011/ 2012+ 2012/ 2013+ 2013/ 2014) xx 0`
` = 0`