Answer:
Approximately, 6.283..
Explanation:
First calculate the area of the whole circle
We have radius(r)=4 cm
Area of circle(a)=pir^2
=pi×(4)^2
=pi×16
=Approximately,50.265......
A cirlce has a total of 360 degrees
Therefore,we can conclude 360 degrees=50.265...
or,1 degree=50.265/360
1 degree=Approximately,0.139
Now,
Area for the shaded region = Area of 45 degree
=0.139×45=Approximately,6.283.....
Therefore,the area of the shaded region is approximately,6.283....