Step 1: Understanding pencil grades
Pencils are graded based on hardness and blackness:
- B (Black) pencils $\Rightarrow$ soft and dark
- H (Hard) pencils $\Rightarrow$ hard and light
- HB pencils $\Rightarrow$ medium hard/dark
Step 2: What is a 2H pencil?
2H is a hard pencil, which produces a light, thin, and precise line.
It is commonly used in technical drawings, blueprints, and initial sketches.
Step 3: Evaluating options
(A) 3B $\Rightarrow$ Very dark line due to softness
(B) 2H $\Rightarrow$ Light line, suitable for fine and clean work
(C) HB $\Rightarrow$ Medium, not as light as 2H
(D) None of these $\Rightarrow$ Incorrect since 2H is correct
\[
\boxed{\text{Correct Answer: (B) 2H}}
\]
Find the unknown frequency if 24 is the median of the following frequency distribution:
\[\begin{array}{|c|c|c|c|c|c|} \hline \text{Class-interval} & 0-10 & 10-20 & 20-30 & 30-40 & 40-50 \\ \hline \text{Frequency} & 5 & 25 & 25 & \text{$p$} & 7 \\ \hline \end{array}\]
Two concentric circles are of radii $8\ \text{cm}$ and $5\ \text{cm}$. Find the length of the chord of the larger circle which touches (is tangent to) the smaller circle.