What does "|" mean in statistics(probability)?

Tell me how you got the it use the figures to answer questions 1and 2. in each diagram, line k is parallel to line l, and line t intersects lines. 1. based on the diagrams, what is the value of x? 2. how would you verify your answer for x?

Arestaurant gives out a scratch-off card to every customer. the probability that a customer will win a prize from a scratch-off card is 25%. design and conduct a simulation using random numbers to find the experimental probability that a customer will need more than 3 cards in order to win a prize. justify the model for your simulation, and conduct at least 10 trials.

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left