Does the BenQ TK700STi have eARC?

No, the BenQ TK700STi does not have eARC (enhanced Audio Return Channel) as it is a projector and not an audio device. eARC is a feature found in audio devices such as AV receivers, soundbars, and TVs, which allows for high-quality audio signals to be transmitted from the TV to an external audio system. However, the BenQ TK700STi does have several audio connectivity options, including a 3.5mm audio jack, an HDMI port, and a built-in speaker.