Answer:
Petra's job title is a researcher
Explanation:
<h2>Who is a researcher ?</h2>
A researcher is someone who takes on a particular project, that involves systematic and organized investigation either to improve on something, make a new finding,or a novel invention or results.
Back to our question Petra can also be called a scientist, analyst, investigator, experimenter, analyzer, tester, and she can work in the research and development (R&D) of a food related industry
