0.55555555555555 as a fraction form?

In two or more complete sentences describe how to determine the appropriate model for the set of data, (1,1), (3,2), (6,3), (11,4).

Two line segments are shown in the figure below. suppose that the length of the line along the x-axis is 6, and the length of the hypotenuse of the triangle is 10. what is the equation of the hypotenuse line (shown in red, below)?

In the equation sqrt(n+5)-sqrt(11-10)=1. what is the value of n