Researchers calculated the amount of time a working couple without children needed to work in order to provide the bare necessities of life. They then compared the calculated time to the amount of time they actually spend on those activities.
वोल्रॉट यांनी हत्तींची सतत ये - जा असलेल्या भागातील काही झाडांवर काही भरलेले आणि काही रिकामे मोहळ लावले.