Help please, i will award brailiest the first correct answer

Bella want to know what the students at her school think of her show. which is the best group to survey to find this information a. go to the mall and ask all of the students she recognizes from school b. ask her viewers to call in durning an episode of the show c. get a list of students at her school from the office and use a random number generator to pick 30 of them d. get a list of students at her school from the office and pick the first 30 students on the list

Idon't get undoing if its pass adding and subtracting so can someone ? x-2 over 5 = 18

Two cities a and b are 1400km apart and lie on the same n-s line. the latitude of city a is 23 degrees. what is the latitude of city b. the radius of the earth is approximately 6400km.