Usually pronounced /ri:-/ for meaning 1, and before an unstressed syllable for meanings 2 and 3. Otherwise the pronunciation is /ri-/ before a vowel sound and /rɪ-/ before a consonant sound.
Re- is added to verbs and nouns to form new verbs and nouns that refer to the repeating of an action or process. For example, to ‘re-read’ something means to read it again, and someone’s ‘re-election’ is their being elected again.
Re- is added to verbs and nouns to form new verbs and nouns that refer to a process opposite to one that has already taken place. For example, to ‘reappear’ means to appear after disappearing, and to ‘regain’ something means to gain it after you have lost it.
Re- is added to verbs and nouns to form new verbs and nouns which describe a change in the position or state of something. For example, to ‘relocate’ something means to locate it in a different place and to ‘rearrange’ something means to arrange it in a different way.