How will "B" in marking period affect admission outlook?
Relax! For starters, colleges only care about your final grade in a class and not your quarter or even semester grade. Your high school will also use your final grade when computing your GPA.
Secondly, even if you were to get a B in pre-calc as your final grade, this will not torpedo your college admission chances. While it’s admirable to aim for top grades, many of the most successful (and happiest) people on the planet were not straight-A students. So keep up the good work, but don’t be too hard on yourself if it’s not always perfect work.