Among fatal plane crashes that occurred during the past 65 years, 374 were due to pilot error, 51 were due to other human error, 659 were due to weather, 565 were due to mechanical problems, and 90 were due to sabotage. Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it?

Alaser tag arena sells two types of memberships. one package costs $325 for one year of membership with an unlimited number of visits. the second package has $125 enrollment fee, includes five free visits, and costs and additional $8 per visit after the first five. how many visits would a person need to use for each type of membership to cost the same amount over a one-year period?

In this food web, which group would increase in number if snakes were eliminated? a. producers b. decomposers c. primary consumers d. secondary consumers e. tertiary consumers

Essay on sustainable development of soiciety