Which ordered pair in the form (a, b) is a solution of this equation?
7a – 5b = 28
a.
(4, 0)
b.
(0, 4)
c.
(–2, –3)
d.
(–3, –2)

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.