Answer:
2.5% of sea water is salt
The sentence that has a verb in the active voice is B. Guglielmo Marconi perfected a type of radio technology.
The rest of the sentences have their verbs in the passive voice. If you wanted to make a passive sentence out of B, you would say - A type of radio technology was perfected by Gugliermo Marconi.
Plagiarism is the act of copying a writer’s words verbatim and claiming them as one’s own.
I had a sense of deja vu when I saw the girl who looked just like her mother used to.
I trust you completely. You have complete carte blanche to arrange the party.
