pa help plssss plsssss

1.If 4 men can build the fence in 10 days , how many men are needed to do the job in 2 days ?

2.The food for 20 dogs will last for 10 weeks. How long will it take for 10 dog ?

3.If a farmer can plow a 3 hectare land in 8 days, how long will 2 farmers do it ?

4.An orphanage can has enough bread to feed 30 orphans for 12 days, if there are 40 orphans, how many days will the same amount of bread last ?​