Pass parameters from UNIX shell to SQL*Plus

[khussain]

(1) How can I pass a parameter value from the shell environemnt to the SQL*Plus environment ?

(2) Also, how can I send the output from sqlplus to a log file when it is run from with a shell script ?
Basically this is what I want to be able to do, but when I do this, the control goes to the log file, and I cannot see what I am typing:

within a schell script
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sqlplus scott/tiger@db1 @sqlSCRIPT.sql > sqlLOG.log
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