# Which men in the army of Israel had to purify themselves?

All the men in the army who had killed anyone or touched a dead person had to purify themselves. 

# How long did the soldiers who had killed anyone or touched a dead body have to camp outside the camp of Israel?

They were to stay outside the camp for seven days. 

# On which days were those soldiers and their prisoners camped outside the camp of Israel supposed to purify themselves?

Those camped outside the camp of Israel had to purify themselves on the third and and seventh days. 