It is important that face masks used by firefighters be able to withstand high temperatures because firefighters commonly work in temperatures of 200-500°f. in a test of one type of mask, 12 of 60 masks had lenses pop out at 250°. construct a 90% upper confidence limit for the true proportion of masks of this type whose lenses would pop out at 250°. (round your answers to four decimal places.)

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. how many seconds are required for the pendulum to move from its resting position and return? enter your answer in the box.

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years