An unknown mineral sample cannot be scratched by glass but can be scratched by a steel file. For identification purposes, how is the mineral's hardness described?

the growth of the plants is affected by the heat of the light. what is the student doing?

the sun creates it's own light, also gives light and life to bunch of stuff like plants,animals,humans etc.photosyntesis is the process of making food which needs sun,water,nutrients etc.

this would be called india