A circular railroad sign had a diameter of 30 inches. What is the circumference of the sign?

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

Write and solve a real word problem that involves determining distance on a coordinate plane

10x − 5y + 14 = 0 whats the answer pls