The equation for the ph of a substance is ph = –log[h+], where h+ is the concentration of hydrogen ions. what is the approximate ph of a solution whose hydrogen ion concentration is 2x10^(-9)?
1.0
2.9
8.7
9.3

Which of these triangle pairs can be mapped to each other using two reflections?

Afarmer has 5 times as many cows as pigs. the farmer only has cows and pigs, and he has 168 animals. how many cows does he have?

Maryann’s friends loved her bulletin board, and 4 of them asked her to make one for their homes. she offered to make each of her friends a replica of her bulletin board that measures 2 meters by 3 meters. how many kilograms of burlap should maryann collect to complete the bulletin boards for her friends? maryann should collect kg of burlap.