Answer: 136 units squared
Step-by-step explanation:
I will assume this is a rectangular prism since it isn't specified.
The surface area of a rectangular prism: SA = 2(lw+lh+wh).
Plugging in your dimensions: SA = 2(7*2 + 7*6 + 2*6) = 2(14+42+12) = 2(68) = 136 units squared.