i do adv so idrk how to explain in stadnard syllabus terms but in a normal distribution is a probability distribution showing like all the probabilities of a continuous random variable, where like the distribution is symmetrical and the mean = median = mode(and this is at the very middle of the distribution), everything is symmetrical to etiher side, and like
a z score is basically a measure of how many standard distributions a score is away from the mean. idk if u need this in standard but theres a formula for it, just search up z score formula. it converts any normal distribution for any numbers into a standardized distribution so then you can use the z-scores to calculate probabilities. u can use the empirical rule for this, basically from -1 to 1 a score 68% of all scores lie within this region, and from -2 to 2 95%, -3 to 3 99.7%. i've done standard questions before and im pretty sure is definitely something u need to know
srory if this is bad but im sure if u look at the notes and resources on BoS there will be some standard notes that u can read up on