Read the text. Before tuning a guitar, first learn the name of each string. A guitar has six: the first
string is on the bottom, and it's the thinnest. The sixth string is on the top, and it's the
thickest. Starting at the bottom, the notes are E, B, G, D, A, and E.
If you have an electric tuner, hold it near the guitar and pluck the high e string (the one
on the bottom) first. The tuner will determine whether the note produced by the string is
flat (too low) or sharp (too high). Pick each of the remaining strings. Depending on what
the tuner tells you, loosen the string to make the note lower or tighten it to make the
note higher.
Which author's purpose is suggested by the text?
to inform readers about the components of a guitar
to persuade readers to buy an electric tuner
to explain how to tune a guitar

every four years the american people choose a new president, and 1988 is one of those years."

21 balloons is the story of professor william sherman's travels.

in 1883, he set off from san francisco for a balloon ride over the pacific and was found a month later floating with 21 balloons in the atlantic ocean. this seemed an astounding feat and everyone wanted to know what had happened.    

professor sherman was loyal, however, and said he would tell his tale first to the western american explorers club in san francisco, of which he was a member. this built up suspense for several chapters before he began to tell of the wonders of his adventures and the amazing island of krakatoa, an island which had just been blown up by a volcano.  

the residents of krakatoa are all millionaires who live under a "gourmet government" of their own devising. we get to see all the incredible adventures that creative people with unlimited resources would create according to the author.