The cricumference formula is given by:
[tex]C=\pi *d[/tex]where C denote the circumference, d the diameter of the circle and Pi is the constant equal to 3.14.
Case 1.
In this case, d=5.5 cm, then by substituting this value into the formula, we get
[tex]\begin{gathered} C=3.14*5.5 \\ C=17.27\text{ cm} \end{gathered}[/tex]Case 2.
Now, by substitutinfg d=8m, into the circumference formula, we get
[tex]\begin{gathered} C=3.14*8m \\ C=25.12m \end{gathered}[/tex]Case 3.
Finally, by substituting d=5.8m into the formula, we obtain
[tex]\begin{gathered} C=3.14*5.8m \\ C=18.212\text{ m} \end{gathered}[/tex]In summary, the answers are:
[tex]\begin{gathered} 1)\text{ C=17.27cm} \\ 2)\text{ C=25.12 m} \\ 3)\text{ C=18.212 m} \end{gathered}[/tex]