Answer:
1.94 kg
Step-by-step explanation:
we have given density of water = 1 gm/

the initial reading of the scale = 19 N
change in reading of scale =10 N
we have to find the mass of the block when the block is lowered in water
mass of the block when it is lowered in the water is given by

here g is the gravity of acceleration which value is given by 9.8

so the mass of the block =
