if a cell measured 0.04 mm and was magnified by 40, what would be the image size?

The image size can be found by multiplying the actual size of the object by the magnification factor. Given:
Actual size = 0.04 mm
Magnification = 40 Image size = Actual size × Magnification
Image size = 0.04 mm × 40 = 1.6 mm The image size would be 1.6 mm.