Woese:. a) was involved in determining rRNA sequences. b) proposed breaking prokayotes into Archaea and Bacteria. c) proposed breaking eukayotes into Archaea and Bacteria. d) was involved in refining the Gram stain for classification purposes. e) a and b

Explanation:

1. Carl Woese, was born in July 15, 1928 is  American microbiologist.

2. Carl Woese discovered the group of single-cell prokaryotic organisms known as archaea, which now constitute a third domain of life.

3. Worse was involved in;  i)determining rRNA sequences and also in ii)he proposed breaking prokaryotes into two groups.

4.The method Woese used, is  called ribosomal RNA.

5. He study rRNA instead of DNA because, RNA is a simpler molecule than DNA.