I think the greatest common factor is 4 x 4.
Answer:
C. 
Step-by-step explanation:
Height = 4
Length = 6
Breadth = 7
Note : We were asked to find volume of the cuboid
Since, it has a base in the shape of a right angle triangle , we need to find the Area of the trapezium before calculating the total volume.
Step 1
Find the area of the trapezium
Area of a trapezium = 



Step 2
Calculate the volume of the cuboid
Volume of a cuboid =length× breadth × height
In this case , the volume will be our length × Area of a trapezium
V= 6 × 22
V = 
Simply divide 3 by 0.7,

Or ≈ 4.28571 which is ≈ 4 years.