None.
Miles is a measure of distance whereas 300000 per second is a measure of frequency. The two measure very different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid.
Approximately 186000 miles/second or 300000 kilometers/second
70 miles per second is 252,000 miles per hour.
52 miles per second = 187,200 miles per hour.
The closest is the speed of light at 299,792,458 kilometers per second.
About 4.7 miles per second.
0.033 miles per second or about 174.24 feet per second.
4.7 metres per second is about 10.5 miles per hour.
186,000 miles per second. This is the 'miles per second' that it takes light to get anywhere in a vacuum.
.8 miles/second
44 mph = 0.012 miles per second
33 miles per second = 118,800 mph
40 feet per second is 27.27 miles per hour.