Lin and Elena each walk 500 units to school. Who walks 500 yards?

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

What 2 forces allow things to fall ‍♀️‍♀️

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)