555 - Astable
R1 =   K
R2 =   K
C1 =   μF

Calculate the astable frequency (f) to 3 sig figs
Astable (pulse output) frequency (f) =  Hz

 
 
For more detail look here
The formula is in the specification. Also, click on 'Help'.
It will be given in the examination.
You will need a calculator!

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