Identify the non-biodegradable wastes from the following:
[I.] Thermal power plants which produce fly ash
[II.] Wastes generated by cotton mills
[III.] Wastes produced by food processing units
[IV.] Slag produced from blast furnace
Identify the correctly matched sets:
CO - neutral oxide GeO - acidic oxide PbO - basic oxide

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:
Group 15 elements are also known as nitrogen group elements or nitrogen family.
It consists of:
They are present on the right side of the periodic table. All the elements are arranged based on their atomic weight. The elements with similar properties reside in a column called the group.
All Group 15 elements have the electron configuration ns2np3 in their outer shell, where n is the principal quantum number.
