Selena is growing geraniums outdoors in a pot. during the day, the temperature in her
area averages 22°c (72°f). at night, the temperature has been dropping to around 13°c
(55°f). what advice would you give to selena and why?

Keep on doing what you are doing.  

Explanation:

These are the ideal temperatures for growing geraniums,

The advice I would give Selena would be that:

Explanation:

Geranium is a plant closely related to spring and summer seasons characterized by medium or high temperatures, so that geranium can withstand regular temperatures of 30 ° C without any problem as it is directly irradiated by the sun, due to its strength towards warm weather, it is extremely weak to cold weather, so a temperature of 10 ° C or lower could wilt it, for this reason, and considering that the temperature at night decreases to 13 ° C (too close to the limit 10 ° C), it is recommended that you enter the plant into your home at night, where the temperature will surely be 2 or 3 ° C higher than outside.