4 6 REVIEW REVIEW Simplify each difference 2 3n 6 3n 4n 7 7n A n 4n 12 6n B n 4n 14 6n C n 4n 12 D n 4n 13 Simplify each sum 4 2x 5 6 2r A 1 C 1 5x 6 A 266 a 1 16a 10 B B 1 x D 3 5x Simplify Your answer should contain only positive exponents ab 2a b 2a 7 2ab D 6 10 5 16a 64 2 3 7 3 6n 5 2n 4 5 8mm A 10n 7n 5 B 10n 8n 5 C 10n 2n 5 D 10m 2n 5 2x 6x 3x x A 7x x 2 C 8x x reserved A 4b C 64a D B 15x x D 14 8b 166