calculate the average speed for the time period $\backslash \{1,2\backslash \},$ we substitute h $=1$ into v avg $=1\mathrm{.}28-1\mathrm{.}86$h $,$ and evaluate. v avg $=1\mathrm{.}28-1\mathrm{.}86(1)$; $=1\mathrm{.}28-1\mathrm{.}86$; $=$ Box m $/$s $($rounded to two decimal places$)$ Similarly, for the time period $[1,1\mathrm{.}5],$ we have the following. v avg $=1\mathrm{.}28-1\mathrm{.}86(0\mathrm{.}5)$; $=1\mathrm{.}28-($ Box$)($d$0$ not round$)$; m $/$ s $($ rounded to two decimal places $)$