The world’s largest ocean, the Pacific Ocean, has an area of about 200,000,000 km2, which can be written as 2 × 10n km2. What is n?

Omar is going on a road trip! the car rental company offers him two types of cars. each car has a fixed price, but he also needs to consider the cost of fuel. the first car costs $90 to rent, and because of its fuel consumption rate, there's an additional cost of s0.50 per kilometer driven.

If i have one apple and give you the apple, how many apples do i have?

What is the missing step in this proof ?