When 18o is struck by a proton, 18f and another particle are produced. what is the other particle? 1. 1 1h 2. none of these 3. 4 2he 4. 2 1h 5. 2 1 0n 6. 1 0n 7. 0 1 e −?

Found this off of google, "A period is a horizontal row of the periodic table. There are seven periods in the periodic table, with each one beginning at the far left. ... A group is a vertical column of the periodic table, based on the organization of the outer shell electrons. There are a total of 18 groups."

Hope this helps, have a great day and stay safe! :) :D :3