Calculation of Overtaking Sight Distance:
The overtaking sight distance is the distance required for a driver to overtake another vehicle safely on a highway. It includes the distance required for the driver to see any oncoming vehicles and also to accelerate and complete the overtaking maneuver.

Components of Overtaking Sight Distance:
The overtaking sight distance consists of three main components:
1. Distance required for the driver to perceive and react to a potential hazard (d1)
2. Distance required for the driver to accelerate and overtake the slower vehicle (d2)
3. Distance required for the driver to return to the original lane safely (d3)

Calculation of d1:
The distance required for the driver to perceive and react to a potential hazard can be calculated using the formula:
d1 = 1/2 * V * T

Where:
V = design speed of the highway (in m/s)
T = perception and reaction time of the driver (in seconds)

Calculation of d2:
The distance required for the driver to accelerate and overtake the slower vehicle can be calculated using the formula:
d2 = (V^2 - V0^2) / (2 * a)

Where:
V = design speed of the highway (in m/s)
V0 = initial speed of the overtaking vehicle (in m/s)
a = acceleration of the overtaking vehicle (in m/s^2)

Calculation of d3:
The distance required for the driver to return to the original lane safely can be calculated using the formula:
d3 = 1/2 * V * T

Where:
V = design speed of the highway (in m/s)
T = perception and reaction time of the driver (in seconds)

Calculation of Overtaking Sight Distance:
The overtaking sight distance (D) is the sum of d1, d2, and d3:
D = d1 + d2 + d3

Calculation of Clearance of Obstruction:
To calculate the required clearance of an obstruction from the center line of a circular curve, we need to consider the horizontal and vertical dimensions.

Horizontal Clearance:
The horizontal clearance is the distance between the center line of the circular curve and the obstruction. It can be calculated using the formula:
Horizontal Clearance = Radius of the Curve - (Width of Lane + Design Offset)

Where:
Radius of the Curve = radius of the circular curve (in meters)
Width of Lane = width of the lane (in meters)
Design Offset = offset distance from the center line to the edge of the lane (in meters)

Vertical Clearance:
The vertical clearance is the distance between the highest point of the obstruction and the highest point of the vehicle. It should be sufficient to allow the vehicle to pass safely without any obstructions.

Final Calculation:
To find the required clearance of the obstruction, we need to consider both the horizontal and vertical dimensions. The final required clearance will be the maximum of the horizontal and vertical clearances.

By calculating the horizontal and vertical clearances and taking the maximum value, we can determine the required clearance of the obstruction from the center line of the circular curve.

Given the radius of the circular curve (350 m), length of the curve (180 m), and width of the lane (1.9