How do i answer this question? Do i use the bernoulli trials? And what do i do when x is greater then n =4?

A dime and two nickels are tossed. Let X be the random variable that calculates the sum of the values of the coins that landheads. Let F (x) be its associated cumulative distribution function. Fill in the following table of values for F (x). WARNING : Do not leave an answer space unfilled before submitting or checking. If an answer space is blank, webwork willmark all your answers as incorrect, irregardless of correctness. F(0) = 1/16F(5) = F(10) =F(15) = F(20) =