Which type of study design generally provides the best evidence of cause-and-effect? Select one: O a. Observational studies O b. Randomized experiments O c. Non-randomized experiments O d. Both b. and c. but not a.While cause and effect can be concluded from randomized experiments, that is generally not the case with observational. studies. The reasons why researchers simply don't conduct all studies as randomized experiments rather than observational studies are: Q a. Observational studies are in general easier to conduct. @b. Randomized experiments are often not feasible because of ethical and/or logistical considerations, @c. The difference between randomized experiments and observational studies is superficial. Od. Both (a) and (b) above Oe. All of (a). (b). and (c) above.Which of the following is NOT an appropriate course of action if data transformation fails to homogen ze variances In an ANOVA? 1. Consider modifying your study design to include larger and/or better balanced samples 1. Conduct the corresponding non-parametric test 1. Conduct the ANOVA anyway, because ANOVA is robust 1. Convert the ANOVA to a series of t-testsQUESTION 5 What is the disadvantage of using 2 one-way ANOVAs instead of conducting a two-way ANOVA? O One-way ANOVAs show only the main effects and not the interactions, You're more likely to violate the homogeneity of variances assumption with a one-way ANOVA. O One-way ANOVAs needlessly raise the power of the statistical tests, O You have to run post-hoc tests if you conduct multiple one-way ANOVAs.For, G(5) = 5/(5 +25+1) Represent this system in 1. controllable canonical form (3) 2. observable canonical form (3) 3. is the system observable (4) 4. is the system controllable (4 )