Answer:
• On earth 73° of latitude is approximately equal to 8154.2 km.
,
• On earth 73° of latitude is approximately equal to 5096.4 mi.
Explanation:
The distance along a line of latitude is calculated using the formula:

Given: θ = 73°, R=6400 km
Then:

On earth 73° of latitude is approximately equal to 8154.2 km.
When R=4000 mi.

• On earth 73° of latitude is approximately equal to 5096.4 mi.