Estimate and determine the order of magnitude of the circumference of the Earth in miles and the speed of a sailboat in miles per hour. The Earth's circumference is 10^4 mile and the the speed of a sailboat is 10^1 mile/hour. Estimate how many hours it would take to sail around the world in a sailboat?

= 1000 hours

Explanation:

Earth's circumference is 10⁴ mile

speed of a sailboat is 10¹ mile/hour

distance = speed × time

10⁴ = 10¹  × t

t = 10⁴ / 10¹

t = 10³

= 1000 hours

answer: option c. i.e. electric current flowing “downhill” from the negative electrode to the positive electrode in a battery

explanation:

the water analogy to the circuits define the pipes (water flows) to the electric current. now, we know that the electric current flows from the positive terminal to the circuit (as shown in the diagram attached).

hence, option c is the correct answer.