brown fracture nonmetallic, grey fracture metallic, yellow fracture concodel nonmetallic, white cleavage 3 directions nonmetallic, white fracture concodel nonmetallic, black fracture nonmetallic -which of the above would be the most difficult to scratch ​

a force of 500                  

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.