HELP. I got these three problems wrong..... I've redone them like 3 times. please help! If you give me the correct answer I will give thumbs up.

Consider the reaction. A(aq) = 2B(aq) Kc = 5.26 x 10-6 at 500 K If a 3.20 M sample of A is heated to 500 K, what is the concentration of B at equilibrium? M [B] = 0.00205134 x10-3 Incorrect Consider the reaction. 2 A(g) = B(g) K= 6.67 x 10-5 at 500 K If a sample of A(g) at 4.30 atm is heated to 500 K, what is the pressure of B(g) at equilibrium? atm Pg = 2.1772 x10-2 Incorrect At a certain temperature, the K, for the decomposition of H, Sis 0.874. H,S(g) = H,(9) + S(g) Initially, only H, S is present at a pressure of 0.185 atm in a closed container. What is the total pressure in the container at equilibrium? atm Protal = 374 incorrect