Find the least number that must be subtracted from 4520 so that the reminder is a perfect square
Answers
Step-by-step explanation:
1. While India’s foodgrain production has risen four-fold in the last 50 years, the growing concern, apart from population growth, is: how far can we stretch agricultural production? Intensive farming, degradation of natural resources and over exploitation of surface and groundwater are fast taking their toll on soil fertility and yield. Maybe, just increasing forest cover can redeem us. 2. The need for forests and other sustainable farming practices is brought out by the Atlas of Sustainability of Food Security in India, published by the M.S. Swaminathan Research Foundation (MSSRF) and the World Food Programme (WFP). The atlas, recently released at the National Food Security Summit, is a timely warning for those who advocate bringing more and more land under the plough. 3. The atlas also warns that shifting to the superior cereals of rice and wheat from coarse cereals and minor millets threatens sustainable food security in two ways. The mono-cultivation of paddy-wheat results in the depletion of organic content and micronutrients in the soil. Chemical fertilizers are required to offset the diminishing returns and achieve the same production level. Also, coarse cereals have a higher nutritive value than rice and wheat and a decline in their intake means a decline in the quality of nutrition. Unfortunately, the area under coarse cereals has fallen, from 30 per cent in 1960 to 16 per cent by the year 2000. Moreover, only 12 per cent of the area under coarse cereals gets irrigation facilities, as against 86 per cent of wheat, 93 per cent of sugarcane and 51 per cent of rice. The latter two consume more water and contribute to desertification in semi-arid regions. 4. Higher levels of crop diversity are necessary for more sustainable food securityand sustainability of livelihoods. It is also important to include leguminous crops in the