What does 5 % mean in math s it like 5/10

Given f(x) = 2x^2- 5x+1, determine the function value f(2). do not f(x) = in your answer

Can someone me with this problem . show your work .

Afarm that has 4 x 10^2 acres has 1.2 x 10^5 cattle. what is the average number of cattle per acre? write the answer in scientific notation. answere asap