Modeling the trading volumes. On July 8, 2020, an article was published in Munich Personal RePEc Archive (MPRA) that introduced a new model with periodic timevarying parameters and a multiplicative error form for modeling trading volumes. The model was used for modeling the daily Bitcoin trading volume (BTV) from July 3, 2017 to June 26, 2020. The full series of volumes has the average of 40.8 and standard deviation of 47.2. Let x represent the daily BTV and let us say it is normally distributed.

a. Find P1x 7 502.

b. Find P145 6 x 6 552.

c. Find P1x 6 1002.

d. Someone says that usually the daily BTV is above 80. Do you agree?