I feel confident about investigating thermal energy/designing a thermal energy device because

simple answers only

I have a solid understanding of the principles and concepts of thermal energy.

I have successfully conducted previous investigations or designs related to thermal energy.
I have received positive feedback or recognition for my previous work in thermal energy.
I have a strong background in relevant subjects such as physics or engineering.
I have access to the necessary resources, tools, and equipment needed for investigating or designing thermal energy devices.