Three Chinese coins, Identification please.

Could I ask for an identification of these three Chinese coins please ? I think that the top left is slightly different in the shape of a character from the other two and the top right and bottom one are identical.
Weight is 4.2 and 4.3g, diameter approx 24mm.
Many thanks.
Brian.

 

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Emperor Gao Zong
Qian Long tong bao
Board of Revenue mint
The two that look similar on the obverse (4 characters) are probably 1736-1773. Hartill 22.201-22.214
The top left one is probably 1774-1795. Hartill 22.215-22.230

 

Many thanks, just what I needed to know.
Cheers
Brian.