Chicos, podrían ayudar me con mi tarea? Esto dice - por q los corredores de una carrera salen del mismo punto?

Compare and contrast physical changes with chemical changes.

Asample of hydrated tin (ii) chloride (sncl2) has a mass of 4.90 g. when it is dehydrated, it has a mass of 4.10 g. which is the correct chemical formula for the hydrate? sncl2•2h2o          sncl2•4h2o          sncl2•6h2o

What is the name of the enzyme that forms at the start of transcription?