what is true about a meta-analysis ?

a, its helps determine whether a studies should be replicated

b it determine and appraises previous research

c, its pools results from previous studies into a single quantitative analysis

d , it replicate previous studies to confirm statistical results

2. The researcher is concerned about internal validity in quasi experimental study, in response, the researcher

a, Increase the sample
b, recognizes that quasi experimental studies are the same as experimental studies

c, randomly assign subjects to experimental and control groups

d, decrease the sample size