10+10 is the same as 11+11

There is diarrhea on the floor. what do i do? my mum gonna see that i diarrhea on the floor! * don't report, i'm serious! *

Answer soon(fast) 15 pts-brainliest? for right answer with small explination a restaurant catered a party for 40 people. a child’s dinner (c) cost $11 and an adult’s dinner (a) cost $20. the total cost of the dinner was $728. how many children and adults were at the party? use the table to guess and check.(i couldn't get the graph onto the question)                                8 children and 32 adults9 children and 31 adults10 children and 30 adults12 children and 28 adults

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