Answer:
for 1 its A or D i think most likely A for 2 its B or C I think most likely C for 3 its C I think 4 is D for 5 Is B i think.
Answer:
It contains a comma splice.
Explanation:
"Don't stack twelve boxes on top of one another" and "it's the twelfth one that will knock down the pile" are independent clauses and should be linked by a colon, semicolon, or conjunction.