For a page-by-page breakdown of every exercise, you can visit specialized Russian educational sites (often referred to as - gotovye domashnie zadaniya ):
Often host scanned images of completed workbooks, though you should verify they match the edition year of your physical book. biologiia 8 klass rabochaia tetrad otvety sonin
Provides video lessons and summaries that correspond to the workbook topics, which can help in filling out more complex descriptive answers. For a page-by-page breakdown of every exercise, you