Start out with an empty list of lists. What are the contents of row 2 after these operations?
BONUS:
Instead of using a 2D array, it is possible, though more complicated, to use a 1D array instead. For example, this would be how to convert a 2x2 array to a 1D array with 4 elements:
Given the index of an element of the 1D array, how can you convert it into the indices for the same element in the 2D array? For example, an index of 1 would be come (0,1) in the 2D array.
4,1,9,1,0