Find the volume and the total surface area of a cuboid ,whose :
l = 3.5 m, b = 2.6 m and h = 90 cm .

Answer

To find the volume and the total surface area of a cuboid with the given dimensions, we can follow these steps:

### Step 1: Convert Height to Meters
Given:
- Length (l) = 3.5 m
- Width (b) = 2.6 m
- Height (h) = 90 cm

We need to convert the height from centimeters to meters.

1 cm = 1/100 m
So,
90 cm = 90/100 m = 0.9 m

### Step 2: Calculate the Volume of the Cuboid
The formula for the volume (V) of a cuboid is:
\[ V = l \times b \times h \]

Substituting the values:
\[ V = 3.5 \, \text{m} \times 2.6 \, \text{m} \times 0.9 \, \text{m} \]

Calculating:
- First, multiply 3.5 and 2.6:
\[ 3.5 \times 2.6 = 9.1 \]

- Now multiply by 0.9:
\[ 9.1 \times 0.9 = 8.19 \]

Thus, the volume of the cuboid is:
\[ V = 8.19 \, \text{m}^3 \]

### Step 3: Calculate the Total Surface Area of the Cuboid
The formula for the total surface area (A) of a cuboid is:
\[ A = 2(lb + bh + hl) \]

Substituting the values:
\[ A = 2(3.5 \times 2.6 + 2.6 \times 0.9 + 3.5 \times 0.9) \]

Calculating each term:
1. \( 3.5 \times 2.6 = 9.1 \)
2. \( 2.6 \times 0.9 = 2.34 \)
3. \( 3.5 \times 0.9 = 3.15 \)

Now, sum these values:
\[ 9.1 + 2.34 + 3.15 = 14.59 \]

Now, multiply by 2:
\[ A = 2 \times 14.59 = 29.18 \]

Thus, the total surface area of the cuboid is:
\[ A = 29.18 \, \text{m}^2 \]

### Final Answers
- Volume = 8.19 m³
- Total Surface Area = 29.18 m²

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