You should focus on the following areas for interview.

1. Yourself: Qualification, Experience, Skills, Projects etc.
2. JPCL: Background, Operating Capacity, Senior Management etc.
3. The Job: Requirement, How you suit the position, academic questions etc.
4. General: Energy Crisis in Pakistan, Sources of Energy, Problems and Solutions

Remember, every job interview focuses on three areas i.e. YOU, THE ORGANIZATION and THE JOB.

I hope you find this helpful.

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And hold firmly to the rope of Allah all together and do not become divided! AL-Quran