Which two sources are secondary sources?
a personal letter
an encyclopedia article
a personal interview
a magazine article
a diary entry

An encyclopedia article and a magazine article

Explanation:

All the other choices are forms of primary sources: Where the person is writing in his/her own words. The encyclopedia and the magazine article are in someone else's words , not the person it's about. Even though there may be quotes from that person, the person themselves didn't write it

you need to include the text. we have no idea what you are referring to

the answer is

r ≈5.641

plug in the area of 100 yards into the equation

100=

divide each side by pi

≈ 31.8309=

take the square root of each side to find r

=r

r ≈5.641