"Which one of the following 4 option combinations leads to a delta-neutral position? , which combination leads to the longest delta position? , which combination leads to the shortest delta position? Which combination leads to a vega-neutral position? : (1) 1-year 25-delta put - 1-year 25-delta call, (2) 1-year 25-delta call + 2-year 25-delta put, (3) 1-year 75-delta call - 2-year 25-delta put, (4) 2-year 40-delta call + 2-year 50-delta put (Answer the questions using a clean integer number with no decimal, no comma, no parentheses)"