To answer this question, we need to understand the syntax and meaning of the given JCL (Job Control Language) statement.
In the given JCL statement, each step is specified with an EXEC statement followed by the PGM (Program) parameter. The TIME parameter is used to specify the maximum CPU time allowed for each step. If the TIME parameter is not specified, the default time limit is used.
Let's go through each option to understand why it is correct or incorrect:
Option A) Step 1 can use 6 seconds of CPU time.
This option is correct because the TIME parameter for Step 1 is specified as (,6), which means that Step 1 is limited to 6 seconds of CPU time.
Option B) Step 2 has no time limitations.
This option is incorrect because there is no TIME parameter specified for Step 2. Without a TIME parameter, the default time limit will be used, which is usually a system-defined value.
Option C) Step 3 can use 15 seconds of CPU time.
This option is incorrect because the TIME parameter for Step 3 is specified as (,15), which means that Step 3 is limited to 15 seconds of CPU time.
Option D) Each step is limited to its specifically mentioned time, but the entire job can only use 10.
This option is correct because the TIME parameter for the entire job is specified as (,10), which means that the entire job is limited to 10 seconds of CPU time. Each step can use its specifically mentioned time limit, but the total CPU time used by all the steps combined cannot exceed the time limit specified for the job.
Therefore, the correct answer is A,D.