Did gladiators sometimes fight noblemen

No, the nobles did not fight with the gladiators. The nobles paid the gladiators large sums of money to attend their parties. Many of the gladiators became idols for the people and they won a lot of money and bought their freedom. It was very expensive to train them, the best fought a few times a year.

a. poison gas was sprayed over battlefields by airplanes to weaken enemy positions before major attacks.