Step 1: Overview of Kodarma
Kodarma, a city located in Jharkhand, is famous for its mica mines. It is one of the largest producers of mica in India.
Step 2: Mica as the Correct Mineral
Mica is a mineral that is found abundantly in the Kodarma region, and it is widely used in the manufacturing of electrical and electronic components due to its insulating properties.
Step 3: Why the other options are incorrect
- (A) Bauxite: Bauxite is mainly produced in the states of Odisha and Gujarat, not Kodarma.
- (B) Coal: Coal is produced in large quantities in regions like Jharkhand's Dhanbad but not primarily in Kodarma.
- (C) Iron-ore: Iron-ore is mainly produced in regions like Odisha and Chhattisgarh, not Kodarma.
Thus, the correct answer is option (D) Mica.
The value of $\dfrac{1+\cot^2 \theta}{1+\tan^2 \theta}$ will be: