The answer must be

since the triangular pyramid has 4 faces and each has an area of 30

we should multiply that by 4 , so :
These are from least to greatest 1.6,1.64,16,4,16.009
39
6^2 + 12 - 3^2
36+12-9
39
The main formula of a suface area of a cube is as follow:
A = 6x a², where a is the edge length
if a= 1.5, so A= 1.5² x 6= 13.5
so the answer is A= <span>13.5</span>