The total surface area (in cm^{2}) of the given cone will be:

- 30π( 1 + √3)
- 900π( 1 - √3)
- 2200π
- 2700π

Option 4 : 2700π

**Formula used:**

The curved surface area of cone = πrl

Area of circle = πr^{2 }

Where l is the slant height of cone and r is radius of circle.

In a right angle triangle

\(cos\theta\ = \ \frac{base}{hypoteneous}\)

**Calculation:**

Let the height of cone is 'h' and slant height of cone is l.

From the above diagram

\(l\ = \ (\frac{30}{cos60^{∘}})\)

⇒ l = 60 (∵ cos60^{∘} = 1/2)

Hence, the total surface area

A = area of circular top + area of lateral surface

⇒ A = π(30)^{2} + π × 30 × 60

⇒ A = 2700π

Hence, total surface area of cone is 2700π.

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