How much water is lost from a farmland of 20000m squared per month, with a evapotranspiration rate of 25l/m square/week and pump delivery of 600l/min? ?

First, we need to calculate the total evapotranspiration rate for the farmland per month:

25 l/m^2/week * 4 weeks/month = 100 l/m^2/month

Next, we need to calculate the total water lost from the farmland per month:

20000 m^2 * 100 l/m^2 = 2,000,000 l/month

Finally, we need to calculate the total water delivered to the farmland per month:

600 l/min * 60 min/hour * 24 hours/day * 30 days/month = 25,920,000 l/month

Therefore, the net water loss from the farmland per month is:

25,920,000 l/month - 2,000,000 l/month = 23,920,000 l/month

So, 23,920,000 liters of water is lost from the farmland of 20000m squared per month.

Step 1: Convert evapotranspiration rate to l/m² per month

25 l/m² per week = 25 l/m² x (1 month / 4 weeks) = 6.25 l/m² per month

Step 2: Calculate total water loss from evapotranspiration

Water loss from evapotranspiration = Evapotranspiration rate x Farmland area
Water loss from evapotranspiration = 6.25 l/m² per month x 20000 m²
Water loss from evapotranspiration = 125,000 l per month

Step 3: Calculate total water pumped

Pump delivery = 600 l/min = 600 l/min x (60 min/hr) x (24 hr/day) x (30 days/month)
Pump delivery = 2,592,000 l per month

Step 4: Calculate net water loss

Net water loss = Water loss from evapotranspiration - Pump delivery
Net water loss = 125,000 l - 2,592,000 l
Net water loss = -2,467,000 l per month

Note: A negative net water loss indicates that the farmland is receiving more water from irrigation than is lost through evapotranspiration.