F. Stone 1 is softer and experienced a greater physical reaction.
Physical reaction is when an object's appearance changes, not the identity (which would be chemical reaction). Because stone 1 is softer, it would be easier to change its physical property. Since stone 2 is harder, it's more durable and therefore harder to change.
By several tries and studies
There was no sunlight, in one way or another sunlight is the source of almost all life on the surface of the earth
I think it is carbohydrates
