Answer:
Step-by-step explanation:
follow the rule of "a weak acid can't make a stronger acid and weak base can't make a stronger base(it's pretty accurate for acid/salt reactions/replacemnts)" the last reactions won't work, but the second to last one will be kbr+pb(no3)2-> kno3 + PbBr2 (this is unballanced.) the first reaction will work. the second one i'm not too sure tbh, but i think it won't work since barium hydroxide's a weak base and if it were to react it would make koh, a super strong base