Answer:
The surface are of a box = 1186.92 mm²
Step-by-step explanation:
Given in question as :
Diameter of cylinder = 18 mm
The height of cylinder = 12 mm
The surface area of cylinder = ( 2××r×h) + (2××r²)
where R is the radius , R = =
Or Radius r = 9 mm
Or, The surface area of cylinder= ( 2××9×12) + 2××(9)²)
Or , The surface area of cylinder=(678.24) + (508.68)
Or ,The surface area of cylinder= 1186.92 mm²
Hence the surface are of a box = 1186.92 mm² Answer