How do you know a number is divisible by 10?

Ineed with math stuff it involves graphs

The approximate line of best fit for the given data points, y = −2x − 2, is shown on the graph.which is the residual value when x = –2? a)–2 b)–1 c)1 d)2

Taber invested money in an account where interest is compounded every year.he made no withdrawals or deposits. the function a(t)=525(1+0.05)^t represent the amount of money in the account after t years. how much money did taber origanally invested?