Negative amplitude means the signal is attenuated relative to a reference point, so if you see e.g. -20dB, it means the signal is 1/10th of the reference value. dB on it's own is unitless, so you will see things like dBm (relative to 1mW â 0dB = 1mW), or dBV (relative to 1V â 0dB = 1V).
In Colorado, the offer is valid at the Denver Zoo and the Denver Art Museum. However, the Denver Art Museum is Sunday only, because they already offer free admission to everyone on the first Saturday of the month. This list does change, so check the Museums on Us website, before you go.
Please look at the time stamp on the story to see when it was last updated. KANSAS CITY, Mo. â Despite the cold, the Kansas City Zoo will offer free admission to some residents of the metro on Monday. Many of the animals at the Kansas City Zoo stay inside during the winter, but there still will be plenty of them to see on Monday when the zoo plans to offer free admission to some area residents.