Answer:
1. Area of the land which can be ploughed daily is 50 hectares (and 70 hectares at higher rate)
2. Area of the field is 700 hectares
Explanation:
Let x hectares be the number of hectares the farmers normally ploughed in a day. At this rate, they will complete the work in 14 days, so they have to plough
Then x+20 hectares is the number of hectares the farmers ploughed in a day when they increased their productivity of work. At this rate, they will complete the work in 10 days, so they have to plough

The work is the same, so

Ploughing 50 hectares each day 14 days in a row they will plough
