The perimeter of a rectangular plot is 180 m and its area is 1800 m². Take the length of plot as x m. Use the perimeter 180 m to write the value of the breadth in terms of x. Use the value of the length, breadth and the area to write an equation in x. Solve the equation to calculate the length and breadth of the plot.

Find the length of the diameter of a circle whose circumference is 44 cm.

Find the perimeter of a semicircular plate of radius 3.85 cm.

Find the radius and circumference of a circle whose area is 144π cm².