This is easy for some people I need help

Will give brainliest sum of arithmetic series (sigma notation) find the numerical answer to the summation given below. (image shown below)

The late fee for library books is $2.00 plus 15¢ each day for a book that is late. if maria’s fee for a late book was $3.20, write and solve a linear equation to find how many days late the book was.

Find the balance at the end of 4 years if 1000 is deposited at the rate of