first find the variance and the average of the numbers,name them s,u then use this equation?:
T=(Xn-u)/(s/sqrt(n)) ~ t(n-1)
a=.99 -> 1-a=.01
p(-Ta/2<T<Ta/2) =p(-T.05<T<T.05) find this from the table of the t distribution.
for 2 is also as above