40 tens regroup through tens

1.       40 tens regroup to tens
40 tens = 40 x 10, because it says 40 tens
so how many tens are there in 400
=> 400 divided by 10
=> 400 / 10
=> 40
Thus, we will regroup 40, by tens 4 times to get the answer
=> 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 + 10

There are 40 10s in 40 tens
Thus the answer when we add this 40 tens is 400

They sought new allies to germany tried to get mexico to join and put pressure on the us. the us joined the allies because of the lucitania

Iknow one of the answers is a and maybe b but not 100% sure about b