Please help me answer number 12

Suppose there is a simple index of three stocks, stock abc, stock xyz, and stock qrs. stock abc opens on day 1 with 4000 shares at $3.15 per share. stock xyz opens on day 1 with 5000 shares at $4.30 per share. stock qrs opens on day 1 with 6000 shares at $4.60 per share. the price of stock abc on day 8 begins at $3.50. the price of stock xyz on day 8 begins at $3.90. stock qrs opens on day 8 with a price of $4.50 per share. assume that each stock has the same number of shares that it opened with on day 1. what is the rate of change of this simple index over 1 week?

Will mark brainliest with 20 points! the table shows how far object 1 traveled as a function of time. *time (seconds) - 2 4 6 8 *distance traveled (feet) - 18 36 54 72 the equation shows how far object 2 traveled in feet as a function of time in minutes. *f(x) = 10x which object traveled at a faster speed? justify your response.

In trapezoid abcd, ac is a diagonal and ∠abc≅∠acd. find ac if the lengths of the bases bc and ad are 12m and 27m respectively.