you want to get from A (the very top very left) to B (the very bottom very right), when you start at A, your vertical and horizontal distance from B are both 2 miles. your horizontal speed is continuously proportional to your vertical displacement from A (every 1 mile south that you go, you travel 0.5 miles less an hour, (if you were to travel 0.5 miles south from A, your horizontal speed would become 1.75mph), (when at A, your horizontal speed is 2mph)). your vertical speed is 1mph. assume that you can drive wherever you want, don't take roads into account. what is the fastest route from A to B?