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.
Plus, all non-military family members receive a $2 discount on day-of, on-site ticket purchases on this holiday. The rest of the year, the Zoo offers a $2 discount to all current and former members of the military, good for the purchase of up to four day-of, on-site tickets per visit. Please brâing a form of military ID with you to receive the discounts.