NIFTY 20th JULY 2021 Expected Levels

After huge crash in the market on 19th and also Global markets are showing weakness 20th July opening is very crucial.
The following are the Resistance and Support levels for the Nifty.
R1-15765
R2-15806
R3-15837
R4-15861
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S1-15740
S2-15724
S3-15702
S4-15669