MUST ANSWER NOW Letters are sent by second class post unless they are
marked first class.
Over a long period of time it has been established that
50% of letters to be posted are marked first class.
In a random selection of 12 letters to be posted,
find the probability that the number marked first class is
(a) at least 2.
(b) fewer than 10.

The weights of players in a basketball league are distributed normally. the distance (d) of each player's weight (w) from the mean of 86 kilograms was computed as follows: d = |w - 86| if d is greater than 7 for approximately 5% of the players, what is the approximate standard deviation of the players' weights? a. 1.75 kilograms b. 3.5 kilograms c. 4.3 kilograms d. 7 kilograms

Question 1 of 10 2 points different groups of 50 graduates of an engineering school were asked the starting annual salary for their first engineering job after graduation, and the sampling variability was low. if the average salary of one of the groups was $65,000, which of these is least likely to be the average salary of another of the groups? o a. $64,000 o b. $65,000 o c. $67,000 o d. $54,000

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)