21. A manufacturer of plasma televisions has determined that the televisions require servicing after a mean of 62 months, with a standard deviation of 4.5 months. What length of warranty should be offered, if the
manufacturer wants to repair less than 1% of the televisions under the warranty? [2]

Which of the following statement about pascal's triangle are true?

Aprofessional hockey team has noticed that, over the past several seasons, as the number of wins increases, the total number of hot dogs sold at the concession stands increases. the hockey team concludes that winning makes people crave hot dogs. what is wrong with the hockey team's conclusion? a) it does not take into account the attendance during each season. b) it does not take into account the number of hamburgers sold during each season. c) it does not take into account the number of concession stands in the hockey arena. d) it does not take into account the number of seasons the hockey team has been in existence.

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota