Answer: Last option is correct.
Step-by-step explanation:
Since we have given that
Dimension of central rectangle is 6 units by 7 units
So, Area of central rectangle is given by
[tex]Length\times breadth=6\times 7=42\ sq.\ units[/tex]
Dimensions of upper and lower rectangle are as follows:
Length = 5 units
Breadth = 7 units
Area of upper and lower rectangle is given by
[tex]2\times length\times breadth \\\\=2\times 5\times 7\\\\=70\ sq.\ units[/tex]
Similarly, dimensions of two triangles are as follows:
Height = 4 units
Base = 6 units
So, Area of two triangles is given by
[tex]2\times \dfrac{1}{2}\times base\times height\\\\=4\times 6\\\\=24\ sq.\ units[/tex]
Hence, Total surface area of the net of an isosceles prism is given by
[tex]42+70+24\\\\=136\ sq.\ units[/tex]
Therefore, Last option is correct.