Ann and Bob are carrying a 18.5 kg table that is 2.25 m long. A 8.33 kg box sits on the table 0.750 m from Ann. How much lift force does Bob exert?

Ascientist notices that an oil slick floating on water when viewed from above has many different colors reflecting off the surface, making it look rainbow-like (an effect known as iridescence). she aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). the index of refraction of water is 1.3