A 45 rpm record typically weighs around 7-9 ounces.
I've seen it called a 45 RPM Adapter.
I'm not sure if it was made available to the public but they had many 45 RPM versions on Green Vinyl but they were for jukeboxes.
No; it was an album track only.
The 45 rpm record was followed by the , which in turn was followed by the eight-track tape player.
No; it was only ever an album track.
A Vinyl disc (record) that spins at 45 revolutions per minute
The most common 33-1/3 RPM record was 12", the 45 RPM was 7", and the 78 RPM was cut in both 12" and 16". Source: Wikipedia "also 10" vinyl"
Walt Disney Records
45 rpm
In the middle 1950s the cost of a record album ranged from $2.98 to $3.98
No; it was only ever an album track.