It changes because radiation always differs in the atmosphere because of the nuclear plants and of pollution around us. Even though it is indoors.
I think it's c because the first 2 it's kind of oves gills and lungs we and fish use theme to live skin i know there a animle that uses it's skin to brith i don;t rember it's name thow sorry i cant spell well but,hope this helped :)
Magnetic forces act at a distance. The opposites attract and pull each other closer
Assuming that’s a right triangle, in this case A^2 + C^2 = B^2 … (16)^2 + C^2 = (25)^2 … C = 19.2 N
