please help with these! all from the same subject matter, data management: probability distribution.

3. In the expansion of (1+ x)", the first three terms are 1 - 18 + 144. Find the values of x and n. 4. In the expansion of (ax+ by) , the coefficients of the first two terms are 128 and -224, respectively. Find the values of a and b. 5. The Flippy-Cutty Game. Flip a fair coin twice. The number of heads that turn up represents the number of cuts that you get from a deck of well-shuffled cards without replacement. If a royal card (K, Q, J, Ace) is chosen, you win $10. If two royal cards are chosen, you win $25. Determine the probability distribution for the random variable "winnings" and then calculate the expected winnings of the game