The value (up to two decimal places) of a line integral:
\(\mathop \smallint \nolimits_{\rm{c}} {\rm{\vec F}}\left( {{\rm{\vec r}}} \right).{\rm{d\vec r}},{\rm{\;for\;F\vec r}} = {{\rm{x}}^2}{\rm{\hat i}} + {{\rm{y}}^2}{\rm{\hat j}}\)
along C which is a straight line joining (0, 0) to (1, 1) is ______
1
0.5
2
0.667
3
1.33
4
1.667