Answer:
T = 3.6 10³ K
Explanation:
A good way to calculate the surface temperature of a star is to approximate it as a black body, and use Wien's displacement law.
λ T = 2,898 10⁻³
In this case they tell us that the light from the star is between red (700nm) and light infrared (2500nm) suppose that the radiation is
λ = 800 nm (near infrared)
T = 2,898 10⁻³ /λ
T = 2,898 10⁻³/ (800 10⁻⁹)
T = 3.6 10³ K