Question

how will you measure the diameter of the moon using parallax method

Answer 1

hope this help u
ur answer is in attachment

Answer 2

Let assume;  

Diameter of Moon = D.

E = Point on the Earth's surface from where we have to see moon by using telescope.

With help of telescope, determine ∠AEB,

Assume;  ∠AEB = Ф

S = Shortest distance between moon and Earth.

Tangent for ∆ABE,

∴ tanФ = $\frac {AB}{S}$

if Ф → 0 then, tanФ ≈ Ф

Hence, Ф = $\frac {AB}{S}$

AB = ФS

Hence, D = parallax angle × S