Define what is the maximum wavelength

Question: Consider a telescope with a small circular aperture of diameter 2.0 centimeters.

Part A If two point sources of light are being imaged by this telescope, what is the maximum wavelength λ at which the two can be resolved if their angular separation is 3.0Ã-10âˆ'5 radians? Express your answer in nanometers to two significant figures. λ = 490 nm

Correct Part B Calculate the angular separation θ1 at which two point sources of wavelength 600 nanometers are just resolved when viewed through a circular aperture of diameter 1.5 centimeters. Express your answer in radians to three significant figures. θ1 = rad