This code snippet calculates the volume and surface area of a sphere given its radius, and then truncates the results to a specified number of decimal places before printing them.

```
import math
def getVolume(r):
return ((4 * math.pi * pow(r, 3)) / 3)
def getSurfaceArea(r):
return 4 * math.pi * pow(r, 2)
def truncate(n, d=0):
m = 10 ** d
return int(n * m) / m
radius = int(input("Please enter radius: "))
volume = truncate(getVolume(radius), 2)
area = truncate(getSurfaceArea(radius), 2)
print("Volume: " + repr(volume))
print("Surface: " + repr(area))
```

```
Please enter radius: 4
Volume: 268.08
Surface: 201.06
```

`import math`

**Purpose**: This line imports the`math`

module, which provides access to mathematical functions like`math.pi`

and`pow()`

.

`getVolume(r)`

```
def getVolume(r):
return ((4 * math.pi * pow(r, 3)) / 3)
```

**Purpose**: This function calculates the volume of a sphere.**Parameter**: The function takes one parameter`r`

, which is the radius of the sphere.**Formula**: The volume of a sphere is calculated using the formula Volume=43πr3Volume=34πr3.`math.pi`

provides the value of π (pi).`pow(r, 3)`

raises the radius`r`

to the power of 3.

**Return Value**: The function returns the calculated volume.

`getSurfaceArea(r)`

```
def getSurfaceArea(r):
return 4 * math.pi * pow(r, 2)
```

**Purpose**: This function calculates the surface area of a sphere.**Parameter**: The function takes one parameter`r`

, which is the radius of the sphere.**Formula**: The surface area of a sphere is calculated using the formula Surface Area=4πr2Surface Area=4πr2.`math.pi`

provides the value of π (pi).`pow(r, 2)`

raises the radius`r`

to the power of 2.

**Return Value**: The function returns the calculated surface area.

`truncate(n, d=0)`

```
def truncate(n, d=0):
m = 10 ** d
return int(n * m) / m
```

**Purpose**: This function truncates a number`n`

to`d`

decimal places.**Parameters**:`n`

: The number to be truncated.`d`

: The number of decimal places to keep (default is 0).

**Calculation**:`m = 10 ** d`

: Raises 10 to the power of`d`

to create a multiplier.`int(n * m) / m`

: Multiplies`n`

by`m`

, converts it to an integer to drop any fractional part, and then divides by`m`

to scale it back down.

**Return Value**: The function returns the truncated number.

`radius = int(input("Please enter radius: "))`

**User Input**: The program prompts the user to input the radius of the sphere. The input is read as a string, converted to an integer using`int()`

, and stored in the variable`radius`

.

```
volume = truncate(getVolume(radius), 2)
area = truncate(getSurfaceArea(radius), 2)
```

**Function Calls and Truncation**:`getVolume(radius)`

calculates the volume of the sphere using the input radius.`truncate(..., 2)`

truncates the volume to 2 decimal places.`getSurfaceArea(radius)`

calculates the surface area of the sphere using the input radius.`truncate(..., 2)`

truncates the surface area to 2 decimal places.

```
print("Volume: " + repr(volume))
print("Surface: " + repr(area))
```

**Output**:- The truncated volume is converted to a string using
`repr()`

and concatenated with the label “Volume: “, then printed. - The truncated surface area is converted to a string using
`repr()`

and concatenated with the label “Surface: “, then printed.

- The truncated volume is converted to a string using

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