Four students out of a class of 18 are being selected to represent the class at the school-wide spelling bee. how many different groups of 4 can be selected

The map shows the location of the airport and a warehouse in a city. though not displayed on the map, there is also a factory 112 miles due north of the warehouse.a truck traveled from the warehouse to the airport and then to the factory. what is the total number of miles the truck traveled?

Me d is also an option but i couldn't get it in the picture

For the sequence [tex]a_{n} = 2n/(n+1)[/tex], what is the value of [tex]a_{10}[/tex]