The concentration of the dissolved oxygen in water depends on several factors like temperature, pressure, salinity and atmospheric condition. The capacity to hold the dissolved oxygen is higher in cold water, this is because of solubility of gases. The concentration of DO in the cold water reaches upto 10 ppm.
So, the correct answer is (A): 10 ppm


In the first configuration (1) as shown in the figure, four identical charges \( q_0 \) are kept at the corners A, B, C and D of square of side length \( a \). In the second configuration (2), the same charges are shifted to mid points C, E, H, and F of the square. If \( K = \frac{1}{4\pi \epsilon_0} \), the difference between the potential energies of configuration (2) and (1) is given by:
The following are the major sources of Water Pollution: