In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: In rats given 1 % BHA , RA co - administered at a dose of 0 . 05 , 0 . 1 , 0 . 2 or 0 . 25 % showed a dose - dependent enhancing effect on the development of the BHA - induced epithelial hyperplasia .
### Output Text:
In rats given 1 % <span class="chemical">BHA</span> , <span class="chemical">RA</span> co - administered at a dose of 0 . 05 , 0 . 1 , 0 . 2 or 0 . 25 % showed a dose - dependent enhancing effect on the development of the <span class="chemical">BHA</span> - induced epithelial hyperplasia . 