A data analyst is working with a data frame named retail. It has separate columns for dollars $($price$\_$dollars$)$ and cents $($price$\_$cents$).$ The analyst wants to combine the two columns into a single column named price, with the dollars and cents separated by a decimal point. For example, if the value in the price$\_$dollars column is $10,$ and the value in the price$\_$centscolumn is $50,$ the value in the pricecolumn will be $10\mathrm{.}50.$ What code chunk lets the analyst create the pricecolumn?

$1$ point

unite$($retail$,$price$,$ price$\_$dollars, price$\_$cents, sep$=.)$

unite$($retail$,$price$,$ price$\_$dollars, price$\_$cents$)$

unite$($retail$,$price$,$ price$\_$cents, sep$=.)$

unite$($retail$,$ price$\_$dollars, price$\_$cents, sep$=.$