$.$ Which of the following statements is correct?$$Check all that apply.

Possible sources of diversifiable risk include inflation and commodity price changes, changes in currency exchange rates, and fluctuations in interest rates.

Systematic risk reflects the risk that remains after an investor has diversified his or her portfolio.

A investor$$s exposure to company$-$specific risk can be diversified away by holding approximately $40$ randomly$-$selected securities in an investor$$s portfolio.