Easy, The elements that are non- metals in solid state at room temperature are: Boron, Carbon, Silicon, Phosphorus,sulfur, Aersenic , Selenium, and tellurium! I am glad I could help ^-^....
There is more than one non metal which is in solid state at room temperature. For example, phosphor, carbon, sulphur. These I am sure of. Other ones like silicium, are partly metal and partly not.
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