One foot is typically used on the brake, however I guess if you're careful you can press the pedal with two if your feet fit on it.
At 20 miles per hour it takes about 60 feet to stop on wet pavement. At sixty miles per hour it takes at least 300 feet to stop.
If it takes 78 seconds to go 55 feet you are traveling at 0.48 miles per hour.
The skateboard is going 4.64 miles per hour.
The car is going 29mph
65 mph = 95.33 feet per second.
116160 feet per hour
You are traveling at 88 feet per second at 60 miles per hour.
40 feet per second is 27.27 miles per hour.
75 miles per hour = 110 feet per second
1 mile is 5280 feet. So, 40 miles per hour is the same as 211,200 feet per hour.
About 70 miles per hour.
At 87 miles per hour you would be traveling 459,360 feet per hour OR 127.6 feet per second.