LPN to BSN Bridge Program. Designed LPNs who want to obtain a Bachelor of Science in Nursing degree; typical program length: 3 to 4 years. A BSN degree is often a requirement for many positions as is the entry point for professional nursing practice.
More quantitatively, since the diverging lens is 28 cm to the right of the converging lens, the object distance is do = 28 cm + 12 cm = 40 cm; this is the distance between the diverging lens and the image formed by the converging lens.
From the center of the lens all the way to where it's object is and it's object is over here which is not 18. That's why it gave you this distance between lenses. The distance between lenses is 33 centimeters. So if the distance from this 1st lens is 18 well the difference has to be equal to this length.