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: METHODS : ASA was administered as a single dose on GD 9 ( 0 , 250 , 500 , or 625 mg / kg ) , 10 ( 0 , 500 , 625 , or 750 mg / kg ) , or 11 ( 0 , 500 , 750 , or 1000 mg / kg ) and from GD 6 to GD 17 ( 0 , 50 , 125 , or 250 mg / kg a day ) in the multiple dose study to SD rats .
### Output Text:
METHODS : <span class="chemical">ASA</span> was administered as a single dose on GD 9 ( 0 , 250 , 500 , or 625 mg / kg ) , 10 ( 0 , 500 , 625 , or 750 mg / kg ) , or 11 ( 0 , 500 , 750 , or 1000 mg / kg ) and from GD 6 to GD 17 ( 0 , 50 , 125 , or 250 mg / kg a day ) in the multiple dose study to SD rats . 