In this task you will be given a list of lists, of numbers. For every inner list, you should multiply every number in that list and put the results in your answer. The output should be a list of numbers with the same length as the number of the lists in the input list.
[[28, 34, -29, -20], [-20, 0], [-13, 13, -22, 15, 3], [22, 28, -12, -29]]