APPS QUESTION 1 : THE LAKE AND THE LOTUS

A lake of 60,000 square feet has a magical power. The power is in the beginning of January it starts to give a lotus, and then on 2^nd January it gives 2 lotuses. After that on 3^rd January it gives 4 lotuses. On 4^th of January it gives 8 lotuses. And it goes on up to 30^th January. On 30^th January the lake is covered with full of lotuses, so that in which date the lake is partially covered by the lotus flowers?

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