4) To find the area of the circle, we will use the formular
[tex]\text{Area of circle=}\pi r^2[/tex]where r is the radius
From the question, diameter = 35
radius = diameter /2 = 35/2 =17.5
substitute the value into the formula
[tex]\text{Area of the circle=}\pi(17.5)^2[/tex][tex]=306.25\pi km^2[/tex]