It looks like you've uploaded an image with some mathematical problems related to areas, perimeters, and fencing costs. Here's a brief summary of the examples from the image:

Example 1: Area, Perimeter, and Cost of Fencing of a Rectangular Field

• Length of the field = 120 m, Breadth = 75 m.
• (i) Area of the field: $120 \times 75 = 9000 \, m^2$
• (ii) Perimeter of the field: $2(120 + 75) = 390 \, m$
• Cost of fencing: $390 \times 40 = 15600 \, \text{Rupees}$

Example 2: Length and Breadth of a Rectangular Field with a Given Area

• The field's area = 3456 m², and the ratio of length to breadth is 3:2.
• Using the formula for area, we deduce the length and breadth, and the cost of fencing.

Example 3: Area of a Rectangular Plot with a Diagonal

• One side = 35 m, diagonal = 37 m. Using the Pythagorean theorem to find the other side (BC).

Example 4: Area of a Square with a Given Diagonal

• Diagonal of square = 8√2 m.
• Using the formula for the area of a square ($\frac{1}{2} \times (diagonal)^2$).

Would you like me to go into more detail on any of these examples or provide further explanations?