Why cant i sigh up for it says "We're sorry" but we are unable to complete your registration at this time"

Which expression calculates the speed in meters per second of an object that travels a distance of 100 m every 20 seconds

Miranda is braiding her hair.then she will attach beads to the braid.she wants 1_3 of the beads to be red.if the greatest number of beads that will fit on the braid is 12,what other fractions could represent the part of the beads that are red?

Use the quadratic formula to solve the equation. if necessary, round to the nearest hundredth. x^2 - 20 = x a. 5, 4 b. -5, -4 c. -5, 4 d. 5, -4