But. The speed of light is approx 3 x 10^8 metres per second. One microsecond is 1 x 10^-6 seconds.
To simplify it even further. Light travels roughly one foot per nanosecond.
One microsecond is 1000 nanoseconds.
One microsecond is ~ 1000 feet not 6,561,679 feet 9 31⁄64 inches (2000 km)