No. While the two official languages of each country are similar, they are not the same, nor are they mutually intelligible languages.
No, they are different languages. Latin is an Italic language from wich all the modern Romance languages (Spanish, French, Portugese, Italian and others) developed. Latvian is a Baltic language. The only other surviving Baltic language is Lithuanian. Baltic languages aren' t part of the Slavic language group (Russian, Polish, Serbian and many more), but they do have more similarities in between them than other groups have.
No! Lithuanians are an entirely different nation. Lithuanians are Baltic, whereas Russians are Slavic, so they're not the same.
No, Israel and Palestine do not speak the same language. Israelis primarily speak Hebrew, while Palestinians primarily speak Arabic.
According to a September 2006 TNS Opinion & Social / Eurobarometer poll, 12% of Latvians support same-sex marriage.
It means that you speak in the same language
The same language I speak in any location.
According to a September 2006 TNS Opinion & Social / Eurobarometer poll, 17% of Lithuanians support same-sex marriage.
You speak the same language you spoke at the beginning of World War I.
For the same reason you speak English. That's their language. (However English is not your native language, I think)
Each person would speak the same language. Same can be said about any language.
Not necessarily. A language family can have dozens of different languages in it.
It is an interesting notion that religious groups "speak" a language. What language does Roman Catholicism speak? What language does Buddhism speak? Some languages are particularly associated with certain religious groups, particularly when the holy writings of the group are written in particular language, but there are quite a large number of Muslims, for example, who do not speak Arabic, or Jews who do not speak Hebrew.