Beta

What is the sum $\sum_{m} e^{i (U_m k + \beta_m)} $ when $U$ and $\beta$ follow different distributions
What is the PDF of beta distribution?How do you find the expected value of a beta distribution?What is the use of beta distribution?What is the mode ...
How to calcuate the beta metrics?
How do you calculate β?How do you calculate beta with example?How do you calculate beta and what does it measure?How do you calculate beta in CAPM? ...