Which expression can be used to determine the length of segment ab?

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 =

You eat 8 strawberries and your friend eats 12 strawberries from a bowl. there are 20 strawberries left. which equation and solution give the original number of strawberries?

Witch represents the inverse of the function f(x)=1/4x-12