AT&amp;T and MCI have protested the tax and pledged to pass the cost on to  MCI charges 5 percent on all out of state long-distance calls, and AT&amp;T charges a flat rate.
( ( ( ( ( ( ( AT&T and ) MCI ) ( have ( ( ( ( ( protested ( the tax ) ) and ) ( pledged ( to ( ( pass ( the cost ) ) ( on ( to ( MCI charges ) ) ) ) ) ) ) ( 5 percent ) ) ( on ( all ( out ( of ( state ( long-distance calls ) ) ) ) ) ) ) ) ) , ) and ) ( AT&T ( charges ( a ( flat rate ) ) ) ) ) . )
(ROOT (S (S (NP (NNP AT&T) (CC and) (NNP MCI)) (VP (VBP have) (VP (VP (VBN protested) (NP (DT the) (NN tax))) (CC and) (VP (VBN pledged) (S (VP (TO to) (VP (VB pass) (NP (DT the) (NN cost)) (PP (IN on) (PP (TO to) (NP (NNP MCI) (NNS charges)))))))) (NP (CD 5) (NN percent)) (PP (IN on) (NP (NP (DT all)) (PP (RB out) (IN of) (NP (NN state) (NN long-distance) (NNS calls)))))))) (, ,) (CC and) (S (NP (NNP AT&T)) (VP (VBZ charges) (NP (DT a) (JJ flat) (NN rate)))) (. .)))
AT&T's flat rate is usually cheaper than MCI's per call tax. 
( ( ( AT&T 's ) ( flat rate ) ) ( ( is ( ( usually ( cheaper ( than ( MCI 's ) ) ) ) ( per ( call tax ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP AT&T) (POS 's)) (JJ flat) (NN rate)) (VP (VBZ is) (ADJP (ADJP (RB usually) (JJR cheaper) (PP (IN than) (NP (NNP MCI) (POS 's)))) (PP (IN per) (NP (NN call) (NN tax))))) (. .)))