Which of these situations gives an expert witness freedom to give opinions in court?
they have never been an expert witness before.
b)
the testimony is not based on sufficient facts or data.
the expert has been unreliable when dealing with the facts of the case.
d)
the expert's scientific, technical, or other specialized knowledge will
the trier of fact to understand the evidence.

Abeverage can is made of 3004-h19 aluminum alloy (elastic modulus 69 gpa, tensile yield strength 285 mpa, density 2.72 g/cm^3). the dimensions on the can are approximated as a thin-walled cylinder with a height of 4.83 inches, diameter of 2.60 inches. empty the can has a mass of 14.2 g. determine: a. the wall thickness of the cylinder b. assuming a pinned-pinned condition what is the critical load? c. assuming a fixed-fixed condition what is the critical load?