<Question>
The volume of a cone is given by the formula $V = \frac{1}{3}Bh$, where $B$ is the area of the base and $h$ is the height. The area of the base of a cone is 30 square units, and its height is 6.5 units. What is the number of cubic units in its volume?
</Question>

<think>
<Plan_1>
Okay, let's see. I need to find the volume of a cone. The formula given is V = (1/3)Bh, where B is the area of the base and h is the height. Alright, so they've given me the area of the base as 30 square units and the height as 6.5 units. 

First, I should recall what each part of the formula represents.

<prompt_1.1> Identify the given values for the area of the base (B) and the height (h) of the cone. </prompt_1.1>
</Plan_1>

<Execution_1>
<execution_1.1>
The area of the base (B) is already provided, so I don't need to calculate that part. The height (h) is also given. So, the formula is straightforward here. It's just plugging in the numbers into the equation.
</execution_1.1>
</Execution_1>

<Plan_2>
Based on execution_1.1:
Let me write down the formula again to make sure I have it right: V = (1/3) * B * h. Yes, that's correct.
They want the volume in cubic units, so the answer should be a number multiplied by cubic units, but since they just want the number, I can focus on the numerical part.

Okay, substituting the given values into the formula.

<prompt_2.1> Substitute the given values of B and h into the formula to calculate the volume. </prompt_2.1>
</Plan_2>

<Execution_2>
<execution_2.1>
B is 30 square units, h is 6.5 units. So, V = (1/3) * 30 * 6.5. Let me compute that step by step.

First, multiply 30 and 6.5. Let me do that. 30 times 6 is 180, and 30 times 0.5 is 15. So, 180 + 15 = 195. So, 30 * 6.5 is 195. Then multiply that by (1/3). So, 195 divided by 3. Let me divide 195 by 3. 3 goes into 19 six times (3*6=18), remainder 1. Bring down the 5 to make 15. 3 goes into 15 five times. So, 65. Therefore, 195 divided by 3 is 65.
</execution_2.1>
</Execution_2>

<Plan_3>
Based on execution_2.1:
Wait, that seems straightforward.

But let me double-check my calculations to make sure I didn't make any mistakes.

<prompt_3.1> Verify the calculations for the volume using an alternative multiplication method. </prompt_3.1>

Alternatively, maybe I can do it another way. Let's see. Maybe multiply (1/3) by 30 first.

<prompt_3.2> Explore an alternative method to calculate the volume by simplifying before multiplying. </prompt_3.2>

Wait, but let me confirm once again. Maybe using decimal multiplication. Let's see.

<prompt_3.3> Confirm the volume calculation using decimal multiplication. </prompt_3.3>

Is there another way to check this? Maybe using approximate values. Let's see, 6.5 is the same as 13/2.

<prompt_3.4> Re-evaluate the volume calculation using fractions to confirm accuracy. </prompt_3.4>

Wait, but just to be thorough, let me check each step again. Maybe I missed a step or something.

<prompt_3.5> Thoroughly check each step of the volume calculation for any potential errors. </prompt_3.5>

Alternatively, if I use fractions the entire time: 6.5 is 13/2.
So, (1/3)*30*(13/2). Let's compute that. 30 divided by 3 is 10, then 10 multiplied by 13/2 is (10*13)/2 = 130/2 = 65.
</Plan_3>

<Execution_3>
<execution_3.1>
Let me compute 30 * 6.5 first. 30 multiplied by 6 is 180, 30 multiplied by 0.5 is 15. Adding those gives 195. Then 195 divided by 3. 3 into 1 is 0, 3 into 19 is 6 (3*6=18), remainder 1. Bring down the 5 to make 15. 3 into 15 is 5. So, 65.
</execution_3.1>

<execution_3.2>
Since B is 30, multiplying 30 by 1/3 gives 10. Then, multiplying 10 by the height, which is 6.5. So, 10 * 6.5 is 65. Oh, that's the same result. So that's another way to compute it. That gives me more confidence that 65 is the correct answer.
</execution_3.2>

<execution_3.3>
So, (1/3)*30 is 10. Then, 10 multiplied by 6.5. 10*6 is 60, 10*0.5 is 5, so 60+5=65.
</execution_3.3>

<execution_3.4>
Then, 30*(13/2) = (30*13)/2 = 390/2 = 195. Then multiply by (1/3): 195*(1/3) = 65. Yeah, same result. So that checks out.

Alternatively, maybe I can think of the formula as one-third of the product of the base area and height. So, if I imagine the cone's volume is a third of a cylinder's volume, which has the same base and height. The cylinder's volume would be B*h, so 30*6.5=195, and a third of that is 65. That analogy helps too. So, if the cylinder is 195 cubic units, the cone is one-third of that, which is 65.
</execution_3.4>

<execution_3.5>
First, the formula: correct. Then substituting B=30 and h=6.5. Correct. Then 30 times 6.5. Let's do that again. 30*6=180, 30*0.5=15. 180+15=195. Yes. Then 195 divided by 3. 3*60=180, so 195-180=15, which is 3*5. So, 60+5=65.
</execution_3.5>
</Execution_3>

<Plan_4>
Based on execution_3.2, execution_3.3, execution_3.4, execution_3.5:
So, all the different methods give me 65. Therefore, I think that's the right answer. 

I don't see any errors in my calculations.
All the different approaches confirm that the volume is 65 cubic units. So, I can be confident that the answer is 65.

**Final Answer**
The number of cubic units in the volume of the cone is \boxed{65}.
</Plan_4>

<Execution_4>
No prompt to execute.
</Execution_4>

<Final_answer>
Therefore, the volume of the cone is $\boxed{65}$ cubic units.
</Final_answer>
</think>