He meant watts per meter, not minute – the strips can be cut and rejoined. As for the 5 Ah, no clue.
The circumference of a monitor is more than 1 m, so a charger of 3 A at least will be necessary for each. This is why I prefer higher-voltage strips where less current is required and higher resistance is tolerable. Anyway, the power is quite high and this could cause overheating problems.