Neptune is an average distance of 4.5 × 10^9 km from the sun. estimate the length of the neptunian year using the fact that the earth is 1.50 × 10^8 km from the sun on average.

164.32 earth year

Step-by-step explanation:

distance of Neptune, Rn = 4.5 x 10^9 km

distance of earth, Re = 1.5 x 10^8 km

time period of earth, Te = 1 year

let the time period of Neptune is Tn.

According to the Kepler's third law

T² ∝ R³

Tn = 164.32 earth years

Thus, the neptune year is equal to 164.32 earth year.

Step-by-step explanation:

It is 140 degrees because triangle AOD is an iso triangle proven with the fact that the diagonals are equal.  angle AEO is 90 degrees because EO is an altitude so then EOA is 40 degrees and AOD is 100 degrees 100+40 =140