from the question;
we are to construct 99% confidence interval. this can be done using
[tex]\bar{}x\text{ }\pm\text{ z}(\frac{s}{\sqrt[]{n}})[/tex]where,
[tex]\bar{x}\text{ = }98.20,\text{ s = 0.61, n = 98 z= 2.576}[/tex]inserting values
[tex]\begin{gathered} 98.20\text{ }\pm2.576\text{ }\frac{0.61}{\sqrt[]{98}} \\ 98.20\text{ }\pm\text{ 2.576}\times0.0616 \\ =\text{ 98.20 }\pm\text{ }0.159 \\ =98.20\text{ + }0.159\text{ or 98.20 - 0.159} \\ =\text{ 98.359 0r 98.041} \end{gathered}[/tex]therefore the 99% confident inter vale is between 98.041 to 98.359