The lifespans of certain batteries are normally distributed. It is found that 15% of battery/less than 30 hours and 10% of batteries last more than 50 hours. Find the mean and standard deviation of the lifespan of the batteries

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

Askyscraper is 396 meters tall. at a certain time of day, it casts a shadow that is 332 meters long. at what angle is the sun above the horizon at that time?

Seattle, washington is known for being rainy. one day last month, 8 inches of rain fell in 1 1/2 hours. what us the rate of the rainfall expressed in ft per plzzz write a proportion i will give you 100 points