Which of the following describes the fuel used in the Beechcraft Travel Air BE-95?

The Beechcraft Travel Air BE-95 is designed to operate on 100LL Avgas, which stands for 100 Low Lead Aviation Gasoline. This type of fuel is specifically formulated for use in piston engines and is widely used in general aviation aircraft. The "100" indicates the octane rating, which is essential for preventing engine knock and ensuring efficient performance, while "low lead" refers to the reduced amount of tetraethyl lead compared to older gasoline formulations, making it more suitable for modern engines that require lower lead content.

In contrast to the other options, jet fuel is typically used in turbine engines, not piston engines like those in the BE-95. Biofuel is a more recent development aimed at reducing aviation's carbon footprint, but it is not commonly accepted in small general aviation aircraft due to compatibility and certification issues. UL91 is another aviation fuel type that is unleaded, but it is not standard for the Beechcraft Travel Air BE-95. Thus, 100LL Avgas is the correct and recommended fuel for this aircraft, ensuring optimal engine performance and adherence to safety standards.