Ms. Sandy bought a package of pencils. Out of every 10 pencils​, 9 are black. If there are 70 pencils in the​ pack, what fraction of the pencils in the pack are​ black? What percent of the pencils in the pack are​ black? What fraction of the pencils in the pack is​ black?

correct choice is b

step-by-step explanation:

when you calculate the average rate of change of a function, you are finding the slope of the secant line between the two points. for the function the average rate of change from point to point can be calculated as

to find the average rate of change from day 2 to day 10, note that at day 2, 8 houses were sold, so a(2,8) and at day 10, 2 houses were sold, so b(10,2). thus,

its an acute right triangle

step-by-step explanation: