The answer is three significant figures. The 1 and the 7 are both significant, because they are non-zero quantities.
This is where significant figures gets a little more complicated, because if a zero is used as a placeholder (i.e. 0.00027 cm) then it is insignificant.
But in the case above, the zero isn't being used as a placeholder, and thus, is significant.
Answer:
D. The small p value and the small effect size suggest that the observed difference between the drug placebo groups are likely to be due to sampling error. This study should be replicated with a larger sample size.
Step-by-step explanation:
The p value is determined for any test before making a conclusion. If the p-value is smaller than critical value then we reject the null hypothesis which means that drug is not effective for the reducing depression. A very small p-value usually lesser than 0.05 indicates strong evidence against the null hypothesis.
(x-1)^2=9 <=> x-1=3 <=> x=4