A container holds two immiscible liquids: a lower layer of density 1000kg/m3 and an upper layer of density 800kg/m3. A rectangular block of dimensions 10cm×10cm×20cm is tied to the bottom such that half its volume is in the lower liquid and half in the upper liquid. If the block's density is 600kg/m3, calculate the tension in the string. (Take g=10m/s2).