(Solved): 1. When a 60N stone is attached to a spring scale and is submerged in water, the spring scale re ...

1. When a $60-\mathrm{N}$ stone is attached to a spring scale and is submerged in water, the spring scale reads $40\mathrm{N}$. What is the density of the stone? 2. A helium balloon lifts a basket and cargo of total weight $2000\mathrm{N}$ under standard conditions, at which the density of air is $1.29\mathrm{kg}/{\mathrm{m}}^3$ and the density of helium is 0.178 $\mathrm{kg}/{\mathrm{m}}^3$. What is the minimum volume of the balloon?