Determine the final account balance of an investment if $300 is invested at an interest rate of 6.75% p. a. compounded semiannually for 20 years. Pls show full working out ty

Aprisoner is trapped in a cell containing three doors. the first door leads to a tunnel that returns him to his cell after two days of travel. the second leads to a tunnel that returns him to his cell after three days of travel. the third door leads immediately to freedom. (a) assuming that the prisoner will always select doors 1, 2 and 3 with probabili- ties 0.5,0.3,0.2 (respectively), what is the expected number of days until he reaches freedom? (b) assuming that the prisoner is always equally likely to choose among those doors that he has not used, what is the expected number of days until he reaches freedom? (in this version, if the prisoner initially tries door 1, for example, then when he returns to the cell, he will now select only from doors 2 and 3.) (c) for parts (a) and (b), find the variance of the number of days until the prisoner reaches freedom. hint for part (b): define ni to be the number of additional days the prisoner spends after initially choosing door i and returning to his cell.

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Finally, the arena decides to offer advertising space on the jerseys of the arena's own amateur volley ball team. the arena wants the probability of being shortlisted to be 0.14 what is this as a percentage? what is this as a fraction? what is the probability of not being shortlisted? give your answer as a decimal.