STEP 1: find base area $ AB $

To find base area $ AB $ use formula:

$$ AB = r^2 \cdot \pi $$

After substituting $r = 7.2\, \text{cm}$ we have:

$$ AB = \left( 7.2\, \text{cm} \right)^{2} \cdot \pi $$ $$ AB = 51.84\, \text{cm}^2 \cdot \pi $$

STEP 2: find lateral area $ AL $

To find lateral area $ AL $ use formula:

$$ A = 2 AB + AL $$

After substituting $A = 899.7984\, \text{cm}$ and $AB = 51.84\pi\, \text{cm}^2$ we have:

$$ 899.7984\, \text{cm} = 2 \cdot 51.84\pi\, \text{cm}^2 + AL $$ $$ 899.7984\, \text{cm} = 103.68\, \text{cm}^2 + AL $$ $$ AL = 899.7984\, \text{cm} - 103.68\, \text{cm}^2 $$ $$ AL = 796.1184\, \text{cm} $$

STEP 3: find height $ h $

To find height $ h $ use formula:

$$ AL = 2 \cdot h \cdot r \cdot \pi$$

After substituting $AL = 796.1184\, \text{cm}$ and $r = 7.2\, \text{cm}$ we have:

$$ 796.1184\, \text{cm} = 2 \cdot h \cdot \left( 7.2\, \text{cm} \right)^{4} \cdot \pi$$$$ 796.1184\, \text{cm} = 14.4\, \text{cm} \cdot h \cdot \pi $$$$ h = \dfrac{ 796.1184\, \text{cm}}{ 14.4\, \text{cm} \, \pi } $$$$ h \approx 17.598 $$

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