Abox has a square base with each side measuring 10 inches. the height of the box is 4 inches. what is the surface area of the box in cubic inches? (show work i dont understand)

1) Area of the square =a²
The base is a square with the side 10 in. So area of the base
A=10²=100 in²
2) We have 2 such squares - bottom and top, Area of the bottom and top =2*100= 200 in²
3) We have 4 side faces that are have side  10 and 4, these faces are rectangles. Area of rectangle =a*b, a=10, b=4
Area of one side face=10*4=40 in²
Area of all 4 side faces = 4*40=160 in²
4) All surface area = area of 2 bases + area of side faces(lateral area)
A=200 in²+160 in²=360 in²
A=360 in²

Answer is a not really sure tho