Can you please help math is so annoying

Which measurement is the most precise? a) 29 cm b) 28.8 cm eliminate c) 28.76 cm d) 28.762 cm

Which is the graph of the piecewise function f(x)? f(x)=[tex]f(x) = \left \{ {{-x+1, x\leq 0 } \atop {x+1, x\ \textgreater \ 0}} \right.[/tex]

Find the slope of the line that contains the following points. r(-2, 4), s(6, -2)