How do i do these repicts i dont know how its math and i have until 12:50 and i have many of them i just need to know how to solve them

Airline passengers arrive randomly and independently at the passenger-screening facility at a major international airport. the mean arrival rate is 10 passengers per minutes. compute the following probabilities. p(x = 4) p(x > 11)

The hawaiian alphabet has 12 letters. how many permutations are posible for each number of letters?

Points a, b, and c form a triangle. complete the statements to prove that the sum of the interior angles of triangle abc is 180