Step 1: Understanding Basic Minerals
Basic minerals are the essential raw materials used for the production of goods and resources, and they are primarily used in construction, manufacturing, and energy production.
Step 2: Why Iron-ore is the basic mineral
Iron-ore is the most fundamental mineral for the production of iron, which is crucial for construction and manufacturing processes. It is a key component of the steel industry.
Step 3: Why the other options are not basic minerals
- (A) Copper: Copper is an important industrial metal, but it is not classified as a basic mineral like iron.
- (C) Mica: Mica is a mineral used in various industries, but it is not considered as basic as iron-ore in terms of industrial production.
- (D) Gold: Gold is a precious metal, not a basic mineral required for broad industrial use.
Thus, the correct answer is option (B) Iron-ore.
$PQ$ is a chord of length $4\ \text{cm}$ of a circle of radius $2.5\ \text{cm}$. The tangents at $P$ and $Q$ intersect at a point $T$. Find the length of $TP$.