In ancient time, deffernt system of units was following in which unit of mass was "`ser`", unit of length was "`gaj`" & unit of time was "`kall`" `1ser=900 gm`, `1gaj=90cm`, `1 kaal=3hr`. A ball of mass `9kg` is moving with velocity `10 m//s`. Then its momentum (`mv`) in ancient system will be `:-`

Options

A. `1.2xx10^(6)` ser `gaj^(-1)`
B. `(10)^(-6)/(1.2)` ser gaj `"Kaal"^(-1)`
C. `1.2xx10^(6)` ser gaj `kaal^(-1)`
D. `120` ser gaj `kaal^(-1)`

Explanation

To solve the problem step by step, we need to convert the given values into the ancient system of units and then calculate the momentum.

### Step 1: Understand the given values
- Mass of the ball = 9 kg
- Velocity of the ball = 10 m/s

### Step 2: Calculate the momentum in SI units
Momentum (P) is calculated using the formula:
\[ P = mv \]
Substituting the values:
\[ P = 9 \, \text{kg} \times 10 \, \text{m/s} = 90 \, \text{kg m/s} \]

### Step 3: Convert the mass from kg to ser
We know:
- \( 1 \, \text{ser} = 900 \, \text{g} \)
- \( 1 \, \text{kg} = 1000 \, \text{g} \)

To convert kg to ser:
\[ 1 \, \text{kg} = \frac{1000 \, \text{g}}{900 \, \text{g/ser}} = \frac{10}{9} \, \text{ser} \]

Thus:
\[ 9 \, \text{kg} = 9 \times \frac{10}{9} \, \text{ser} = 10 \, \text{ser} \]

### Step 4: Convert the velocity from m/s to gaj/kall
We know:
- \( 1 \, \text{gaj} = 90 \, \text{cm} \)
- \( 1 \, \text{m} = 100 \, \text{cm} \)

To convert m to gaj:
\[ 1 \, \text{m} = \frac{100 \, \text{cm}}{90 \, \text{cm/gaj}} = \frac{10}{9} \, \text{gaj} \]

Thus:
\[ 10 \, \text{m/s} = 10 \times \frac{10}{9} \, \text{gaj/s} = \frac{100}{9} \, \text{gaj/s} \]

### Step 5: Convert the time from seconds to kall
We know:
- \( 1 \, \text{kall} = 3 \, \text{hr} = 3 \times 3600 \, \text{s} = 10800 \, \text{s} \)

To convert seconds to kall:
\[ 1 \, \text{s} = \frac{1}{10800} \, \text{kall} \]

### Step 6: Calculate the momentum in the ancient system
Now we can express momentum in the ancient system:
\[ P = (10 \, \text{ser}) \times \left(\frac{100}{9} \, \text{gaj/s}\right) \]

To convert the time to kall:
\[ P = 10 \, \text{ser} \times \frac{100}{9} \, \text{gaj} \times \frac{10800 \, \text{s}}{1 \, \text{kall}} \]

### Step 7: Simplify the expression
\[ P = 10 \times \frac{100 \times 10800}{9} \, \text{ser gaj/kall} \]
\[ P = \frac{1080000}{9} \, \text{ser gaj/kall} \]
\[ P = 120000 \, \text{ser gaj/kall} \]

### Final Answer
The momentum in the ancient system is:
\[ P = 1.2 \times 10^6 \, \text{ser gaj/kall} \]