Please help me! 15. What is the amplitude of the wave in the diagram? What is the wavelength?

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Pls will give brainliest and all p. s u can zoom in if u cant see plss

Okay so i didn't get this problem petro bought 8 tickets to a basketball game he paid a total of $200 write an equation to determine whether each ticket cost $26 or $28 so i didn't get this question so yeahyou have a good day.