"Musea" is acceptable, and arguably more correct. However... the current, mainstream, usage is: "museums".
The plural form of the noun museum is museums.The plural possessive form is museums'.Example: All of the museums' hours are posted on the main website.
The noun passes is the plural form for the singular pass. Example: The museum passes for the students are here. The word passes is also the third person, singular, present of the verb to pass.
The plural form for the demonstrative pronoun this is these.
The plural form of the word inferno is infernos.
The plural form is ranches.
The singular noun is museum, the singular possessive form is museum's.The plural noun is museums, the plural possessive form is museums'.
There is no plural word for if.
There is no plural form for the word, countries. This word itself is a plural.
The plural form is data.
The plural form of the word "baby" is "babies."
The plural form for the word 'pioneer' is pioneers.
The plural form of the word "pharynx" is "pharynges."