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We put 10 orange balls, 10 red balls, and 20 yellow balls in an urn. We randomly select 6 balls from the urn. What is the probability that two of the balls selected are orange and the other four selected are not orange (either yellow or red)? Round your answer to 3 digits after the decimal point.

Donald believes the COVID-19 virus is produced by a secret lab in China. He searched online and found a news article stating the same thing. He now believes it even more. What decision-making error did Donald fall prey to?

Tamara is on her high school’s soccer team.  In their first game of the year, Tamara’s team lost 3-0. Tamara thought the other team was talented, but not overly mean or aggressive. On the bus ride back home, Tamara’s two best friends on the team, Jocelyn and Christina, spent the whole bus ride talking about how players on the other team pushed, elbowed, and were incredibly over-aggressive. Five weeks later, Tamara is preparing to play another game against the same team from the first game.  When Tamara thinks back to the first game, she now remembers the opposing team being super aggressive and sometimes even cheating.    Tamara’s altered (i.e., changed) memory of the first soccer game is an example of which type of memory error?

for the function h(x)=2×4−6×3+2×2+6x−4= 2(x+1)(x−1)2(x−2), find: (A)  the x-intercept(s), if any

g(x) = x3 – 4×2 + x + 6 has an x-intercept at (1, 0).

The following data represent the time, in minutes, that a patient has to wait during 5 visits to a doctor’s office before being seen by the doctor: 12, 25, 33, 20, 4 We wish to conduct a hypothesis test on the 60th percentile. H0:

What is the median (50th percentile) of X? 

The Welch-Satterthwaite approximation says to pool the variances of the two samples to find an approximation for the population variance. 

Stop! Before submitting your exam: Show all sides of your scratch paper to the camera. Be sure that you are completely finished before you click submit.

A certain facility produces drill bits which are made of either steel, cobalt, or diamond. Suppose that 60% of the drill bits are steel, 25% are cobalt, and 15% are diamond. Further, suppose that 10% of the steel drill bits fail, 5% of the cobalt drill bits fail, and 1% of the diamond drill bits fail. What is the probability that the drill bit is steel and fails?