I need help with my homeworks . Maybe somebody knows how to solve these 3 tasks.

P.S. Thank you very much

1. A student studying for a vocabulary test knows the meanings of 12 words from a list of 20 words. If the test contains 10 words from the study list, what is the probability that at least 8 words on the test are words that tha student knows?

2. A biology quiz consist of 8 multiple-choice questions. 5 must be answered correctly to recieve a passing grade. If each questions has 5 possible answers, of which one is correct.What is the probability that a student who guesses at random on each question will pass the examination?

3. A panel of 64 economists was asked to predict the average unemployment rate for the upcoming year. The results of survey follow:

Unemployment rate,% 4.5 | 4.6 | 4.7 | 4.8 | 4.9 | 5.0 | 5.1 |

Economists''''''''''''''''''''''''''''' 2 | 4 | 8# | 20 #| 14 | 12 | 4 |

Based on this survey, what does the panel expect the average unemployment rate to be next year?

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