i am trying to chart 2 different sets of data:

1. average temperature for various cities in both celsius and fahrenheit.
PROBLEM: if i have celsius on the primary x axis and the fahrenheit on a
secondary x axis it gives me 2 columns. i want one column per city which will
give me the temp in celsius on the primary x axis and the corresponding
fahrenheit temperature on secondary y axis (conversion of celsius to
fahrenheit done with formula of celsius temp*9/5+32). can this be done?

2. i am charting rainfall in 5 cities over 12 months but the data range is
very wide. one of the cities has 10x more rain than 3 of the other cities.
this makes it almost impossible to read the chart. if i plot that city on a
secondary axis, when someone else looks at my chart, how can they know what
city corresponds to primary x axis values and what corresponds to secondary x
axis values? it is very confusing.

fern