Which of the following statements are true?

-An object can experience both tensile and compressive stresses at the same time.
-Strain is characterized by the strength of the forces causing deformation, on a "force per unit area" basis.
-Stress is characterized by the strength of the forces causing deformation, on a "force per unit area" basis.
-The elastic modulus can be determined from the ratio of the strain to the stress.
-Two materials may have similar elastic constants but have vastly different breaking stresses.