Try something like this:
col = 2; % Whatever it is...
theColumn = x{:, col}; % Extract column 2 as a cell array from the table.
rowsToDelete = contains(theColumn, ' ');
x(rowsToDelete, :) = []; % Delete all rows where a space was in col 2
If that doesn't work, attach x in a .mat array:
save('answers.mat', 'x');
and attach it with the paper clip icon.
