Why do scientists conduct experiments ?

Asun-sized star will spend most of its lifetime as a: white dwarf red giant protostar main-sequence star

A150 w lamp emits light of wavelength 590 nm uniformly in all directions. what is the photon flux (photons per unit area per unit time) on a small screen at a distance 2.3 m from the lamp? assume the photons are uniformly distributed over the surface of a sphere of radius 2.3 m.

More solar radiation is absorbed by earth’s surface than by