Urgent* fred writes the expression 4(b − 1) + 10 for the number of tiles in each border, where b is the border number, b ≥ 1. a. explain why fred's expression is correct. b. emma wants to start with five tiles in a row. she reasons, “fred started with four tiles and his expression was 4(b − 1) + 10. so if i start with five tiles, the expression will be 5(b − 1) + 10. is emma’s statement correct? explain your reasoning. c. if emma starts with a row of n tiles, what should the expression be?