math
posted by Jessy .
In a factory of electronic items, the total cost of production, expressed in thousands of dollars, is given by the function C(x)= (x^2x+2)/x+1
where x belongs to [0;5] and expressed in hundrends of items produced.
1) calculate in dollars the total cost of production of 400 electronic items.
deduce that the average cost of one electronic item is $7.
2) calculate the minimum total cost.
3) Each item is sold for $58.Express the income from selling all the quantity produced as a function of x.
4)determine the profit achieved upon selling all the quantity of x and denote it by p(x).

please I desperately need an answer!!