菜鸟请教一道算法题

Given an array of n elements with arbitrary random valus, we want to obtain the smallest logn elements in sorted order. Outline how each of hte following methods be adapted to solve this problem( if appropriate), provide a very brief ex[lanation. And Analyze the worst-case time complexity for each case

1. Radix-sort
2. Bubble-sort
3. Heap-sort
4. linear-time selection( median of medians for pivot)
5. Insertion-sort

我不太清楚用基数排序该怎样去排，希望高手指点。