Can someone help me state whether the graph represents a function or not??!

The hypotenuse of an isosceles right triangle is $14\sqrt 2$. what is the area of the triangle?

The customer price index(cpi), which measures the cost of a typical package of customer goods,was 208.8 in 2011 and 244.1 in 2016.let x=11 corresponding to the year 2011 an estimate to cpi into 2013 and 2014. assume that the data can be modeled by a straight line and the trend to continue idenfinitely.use data points to find such a line and then estimate the requested quantities

What is the measure of sty in oo below? 130 310 230 50