The pH of the water is not a measure of the strength of the acidic or basic solution and alone does not provide a full picture of the characteristics or limitations with the water supply. In general, a water with a low pH (< 6.5) could be acidic, soft, and corrosive.
Price of a Stamp. The current price of a first class stamp is 49 cents. A domestic first class letter (1 oz.) is 49 cents. The price of each additional ounce is 21 cents. It will cost you 34 cents to send a domestic postcard.
The price of a Forever Stamp (one ounce First Class stamp that auto-adjusts to the current postage rate) is $0.49. The last rate change occurred on January 22, 2017. The next rate increase will be to $0.50 on January 21, 2018.