Can someone give me a easy definition of juxtaposition?

This excerpt is from the poet by alfred lord tennyson the poem describes a poets consciousness and perception which three lines suggests the richness of a poets thoughts

Identify whether each detail takes place in the story “the adventure of the speckled band” or in its film adaptation, the speckled band. roylott has a baboon and a leopard, which he brought from india. holmes and watson operate out of their shared apartment at 221b baker street. roylott has a baboon and a cheetah, which he brought from india. holmes and watson operate out of a fancy office with modern conveniences, such as an intercom.

Which sentence is punctuated correctly? the shoes normally cost 40 dollars, however; we got them on sale. the shoes normally cost 40 dollars however we got them on sale. the shoes normally cost 40 dollars, however, we got them on sale. the shoes normally cost 40 dollars; however, we got them on sale.