Danna purchased a tv for $200 eight months later the same tv was selling for $160 what was the percent of decrease in the price

If a flying disk is 139 meters in the air and travels at an average of 13 m/s how long is it in the air

What are the triple angle formulas? is it related to double angle identities?

An observer(o) spots a plane(p) taking off from a local airport and flying at a 29 degree angle horizontal to her line of sight and located directly above a tower(t). the observer also notices a bird circling directly above her. if the distance from the plane(p) to the tower(t) is 6,000ft., how far is the bird(b) from the plane(p).