Target $($retail chain$)$ plans to enter and open stores in Country ABC which has high consumer animosity against the U$.$S$.$ It wants to find out what marketing strategy can effectively lower consumer animosity of the countrys consumers and make them welcome the chain. Towards the efforts, Target plans to conduct causal research by a $2$ by $2$ experimental design, in which y $($purchase intention at Target$)$ depends on x$1$ and x$2,$ which are expected to have a significant interaction effect with each other on y$\mathrm{.}9.($a$)$ Name x$1$ and x$2.($b$)$ Why do they have interaction effect with each other on purchase intention at Target?$10.($a$)$ Write the hypotheses showing the interactive effect of x$1$ and x$2$ on y$.($b$)$ Express the hypotheses on a graph. Put x$1$ on the horizonal axis.