Answer:
406
Explanation:
A rectangular prism has six sides, three pairs of matching ones
Start by finding the area of each of the three kinds of sides
14 x 5 = 70
5 x 7 = 35
7 x 14 = 98
Now multiply each of these answers by two, for the number of sides that have each surface area
140
70
196
Finally, add all of the areas together to find the surface area of the whole shape.
140 + 70 + 196 = 406