Given the function f(x)=1/2x^2+2x-5 what is the value of f(10)

On a trip, you had to change your money from dollars to british pounds.  you got  560  pounds for  800  dollars.  which is a unit rate that describes the exchange

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).

Sasha drank 8 bottles of water everyday for a week. how many bottles of water did she drink in total?