The average life of light bulbs produced by SABA Electric Co. is expected to be normally distributed with the mean service life of 950 hours and standard deviation of 100 hours. A random sample of 100 bulbs is tested and it has a mean life of 910 hours. Can researcher conclude that the mean service life of the bulbs is less than the expectation? H0 is null hypothesis, and Ha is alternative hypothesis. Which method can researcher use to check the idea?

Hell . what are the solutions to `10x^2 - 38x - 8 = 0`? is this when i find the factors and use the numbers within the factors to determine the zeros? i hope that made sense lol

In a test for esp (extrasensory perception), a subject is told that cards only the experimenter can see contain either a star, a circle, a wave, or a square. as the experimenter looks at each of 20 cards in turn, the subject names the shape on the card. a subject who is just guessing has probability 0.25 of guessing correctly on each card. a. the count of correct guesses in 20 cards has a binomial distribution. what are n and p? b. what is the mean number of correct guesses in 20 cards for subjects who are just guessing? c. what is the probability of exactly 5 correct guesses in 20 cards if a subject is just guessing?

Which two transformations are applied to pentagon abcde to create a'b'c'd'e'? (4 points) translated according to the rule (x, y) ? (x + 8, y + 2) and reflected across the x-axis translated according to the rule (x, y) ? (x + 2, y + 8) and reflected across the y-axis translated according to the rule (x, y) ? (x + 8, y + 2) and reflected across the y-axis translated according to the rule (x, y) ? (x + 2, y + 8) and reflected across the x-axis