What is meaning of +- 4D in eye for job application requirement

power 4dReal Time Live 4D Draw Results (Keputusan 4D) - Magnum 4D, Sports Toto 4D, Da Ma Cai, Sabah 88 Lotto 4D, Sarawak Special Cash Sweep 4D, STC 4D, Singapore PoolsTo find the focal length of the combination of two thin lenses in contact, we can follow these steps: Step 1: Identify the Powers of the Lenses We have two lenses: - Lens 1 has a power ( P1 = +4