I need help fast
please help

Which matrix multiplication is possible?

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

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made