7. Expand and simplify the following: A. 7(3n - 9n + 8) - 8(-3 - 10n + 4n)
B. (n - 9) (n - 8) + 3(4n = 5)

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.