Oklahoma City is the answer
The correct options are:
- Improved engines; engines were improved significantly so that they can have the same power and agility but by using less fuel.
- Cleaner burning fuels; it has been invested a lot of time and money into improving the fuels and making them as effective as possible but also removing or lowering the most dangerous components towards the environment.
- Catalytic converters; this devices for exhaust emission control manage to convert the toxic gasses and polutants into less toxic pollutants by managing to catalyze a redox reaction.
It is showing the most populated areas at that time range
It is only logical that mountain ranges form natural watershed boundaries because <u>water </u><u>from </u><u>rain </u><u>and </u><u>melting snow </u><u>flow to the </u><u>river</u>s.
<h3>Sources of Water for rivers. </h3>
- Rainfall and the resulting runoff.
- Water from natural ice.
Both of these come down from mountains and will be impacted by gravity to keep flowing downwards. This then forms or contributes to rivers and explains why mountains are generally next to watersheds.
Find out more on the <u>effects of mountains and rivers</u> at brainly.com/question/9606094.
The number of people per square mile is the population density
