Ineed some with some history questions

1.what made mustard gas for effective?
a. it was effective in stopping air attacks
b. it didn't need to be inhaled to be effective
c. it was colorless
d. it caused instant death rates

2.why did people inside of tanks often pass out?

a. they had very little training

b. it was so fast

c. they were terrifed
d. it was very hot and there was nothing seperated them from engines and fumes