71.7 x 149.6 x 7.2 mm
Wireless charging
，这一点在体育直播中也有详细论述
Last year, we saw savings across all of Amazon's device lineups: Echo, Fire TV, eero, and Kindle. In fact, the Kindle Colorsoft saw its first-ever sale last year. But will this sale beat Amazon's Black Friday pricing? That's still to be seen.
Therefore, evaluating s(x) at , we get: