In a convex lense f=20cm, m=1,then what is u and v?

I'm not sure if I know whatever the answer is

spectral lines lyman is one set

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

hope this : d