Answer:
49 - 9π
Step-by-step explanation:
Area of white portion = area of triangle - area of circle 
To find the area of the triangle: 
The area of a triangle can be calculated using this formula
 where b = base length and h = height
 where b = base length and h = height 
The height given is 7m and the base length given is 14m 
That being said we plug in the given values into the formula

Hence, the area of the triangle is 49 sq meters. 
To find the area of circle
( note that the area is in terms of pi; shown by the answer choices. ) 
Formula for area of a circle = 
We are given the diameter  ( 6m ) 
However, we need the radius
To convert diameter to radius we divide by 2
6/2 = 3 so the radius = 3m 
Now we plug in 3 into the formula

Remember we do not apply pi because the answer should be in terms of pi. 
Now we subtract the two 
Area of white portion = 49 - 9π
Hence, the answer is A