Crude oil is sold in barrels. A cylindrical barrel (drum) contains 42 gallons of oil. The diameter of this barrel is 18 inches.

You may use the following information:

- 1 gallon $= 3.78541$ liters
- 1 inch $= 2.54$ cm
- $1 \text{ ml} = 1 \text{ cm}^3$
- Volume $= \pi \times r^2 \times h$, let $\pi = 3.142$
- Surface area of a cylinder with a closed lid and base $= \left(2 \times \pi \times r^2\right) + (2 \times \pi \times r \times h)$

Use the information above to answer the questions that follow:

3.2.1 Determine the radius of a barrel (drum) in centimeters. (3 points)

3.2.2 Show, using calculations, that the height of the barrel of oil is $96.82$ cm. (5 points)

3.2.3 Calculate the surface area of this barrel in $m^2$.

3.3 The moisturizing gel that the hairdresser uses when relaxing hair is sold in cylindrical containers with a volume of $500 \text{ ml}$ and a radius of $4.5 \text{ cm}$.

Use the information above to answer the questions that follow:

3.3.1 The hairdresser needs to calculate the height of each container to determine how many containers she can stack on a shelf. Calculate the height using the following formula:
\[ \text{Height of a container} = \frac{\text{Volume}}{\pi \times r^2}, \text{ using } \pi = 3.14 \text{ and } 1 \text{ ml} = 1 \text{ cm}^3 \]

3.3.2 The wholesalers have a promotion on the moisturizing gel. They are now selling 600 ml of the moisturizing gel for the same price as 500 ml of the same gel. Calculate the percentage increase in the volume of the moisturizing gel using the following formula:
\[ \text{Percentage increase} = \frac{\text{new volume} - \text{original volume}}{\text{original volume}} \times 100\% \]

[Total: 33 points]