Where would you look for the youngest stars in the milky way galaxy?

Most energy in an ecosystem comes originally from_

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?

If anyonee has done the momentum lab practical in physics can you give me the answers i am s lostt rnn : (