Question is on photo but i thnk its 4

Timed*** there are 8 rows and 8 columns, or 64 squares on a chessboard. suppose you place 1 penny on row 1 column a, 2 pennies on row 1 column b, 4 pennies on row 1 column c, and so on … how many pennies are on each square? a =   b =   c = d =   e =   f = g =   h =

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

You buy 4 items that cost 2.69 14.45 8.05 13.95 what is the estimated total round to the nearest dollar