Write the equation..I already have the answer

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry

Harry and jay are both flying on the same plane with an airline that randomly assigns seats to passengers. of the 182 total seats on the plane, 62 are window seats, 58 are middle seats, and the rest are aisle seats. what is the approximate probability that both harry and jay will be assigned aisle seats on the same plane? a. 11.48% b. 3.3% c. 2.08% d. 26.26%

Whats are the trickiest steps to do when adding or subtracting rational expressions? how does knowledge of rational numbers u in adding and subtracting rational expressions?