Me with the last two shown in picture image

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal.b. he is determining chemical properties that are sufficient to identify the metal.c. he is determining physical properties that are insufficient to identify the metal.d. he is determining chemical properties that are insufficient to identify the metal.

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit