Suppose that the life expectancy of a certain brand of nondefective light bulbs is normally distributed, with a mean life of 1900 hr and a standard deviation of 100 hr. if 40 comma 000 of these bulbs are produced, how many can be expected to last at least 1900 hr?

Afamily has five members. a mom, a dad, two sisters, & a brother. the family lines up single file. what is the probabillity that the mom is at the front of the line

Someone answer asap for ! a ball is rolled down a ramp. the height, f(x), in meters, of the ball x seconds after it is released is modeled by the function f(x) = x²- 10x + 25 for all values of x from 0 to 5. which statement about the ball is true? a. the maximum height of the ball is 5 meters b. the height of the ball increases from 0 to 5 meters above the ground. c. the ball has traveled 5 meters when it reaches the bottom of the ramp. d. the ball has been traveling for 5 seconds when it reaches the bottom of the ramp

Having a hard time understanding this question (see attachment).