To find the volume in cubic meters given in kilolitres, we can make use of the provided conversion table for volumes in different units. According to the table, 1 cubic meter (\(1 m^3\)) is equivalent to 1 kilolitre (\(1 k \ell\)).
Given that we have 251 kilolitres, we can directly convert this to cubic meters using the equivalence provided:
[tex]$[tex]$251 k \ell = 251 m^3$[/tex]$[/tex]
Thus, the blank can be filled in with:
[tex]$[tex]$ 251 k \ell = 251 m^3 $[/tex]$[/tex]