Find n[p(a)] and n[p(b)] where a={x; x is a vowel of english alphabet} and b={x; x^2+3< 2,x€n}

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?

In 2009, there were 1570 bears in a wildlife refuge. in 2010, the population had increased to approximately 1884 bears. if this trend continues and the bear population is increasing exponentially, how many bears will there be in 2018?