statistics.

Treatment for Cocaine Addiction Cocaine addiction is very hard to break. Even among addicts trying hard to break the addiction, relapse is common. (A relapse is when a person trying to break out of the addiction fails and uses cocaine again.) A study is conducted to investigate the effectiveness of two drugs, desipramine and lithium, in the treatment of cocaine addiction. The subjects in the sixweek study were cocaine addicts seeking treatment. The 72 subjects were randomly assigned to one of three groups (desipramine, lithium, or a placebo, with 24 subjects in each group) and the study was double-blind. Now we are able to consider all three groups together and test whether relapse rate differs by drug. Ten of the subjects taking desipramine relapsed, 18 of those taking lithium relapsed, and 20 of those taking the placebo relapsed. (a) Create a two-way table from the information given. Relapse No relapse Desiprami ne 10 14 Lithium 18 | 6 Placebo 20 | 4 Total 48 | 24 \f(c) If it is appropriate to use a chi-square test, complete the test, give the chi-square statistic, the pvalue, and an informative conclusion. Round your answer for the chisquare statistic to one decimal place, and your answer for the p-value to three decimal places