In three years, 30% of a radioactive element decays. Find its half-life. (Round your answer to one decimal place.) yr

Which must be true in order for the relationship △zyv ~ △xwv to be correct? zy ∥ wx ∠z ≅ ∠y and ∠w ≅ ∠x zv ≅ vy and wv ≅ vx ∠z ≅ ∠x and ∠w ≅ ∠y

The numbers on a football field indicate 10 yard increments. you walk around the perimeter of a football field between the pylons. you walk a distance of 30623 yards. find the area and perimeter of the indicated regions. write your answers as mixed numbers, if necessary. a. one end zone: perimeter: yd area: yd2 b. the playing field (not including end zones): perimeter: yd area: yd2 c. the playing field (including end zones): perimeter: yd area: yd2

In which quadrant does the point lie? write the coordinates of the point. a. quadrant ii; (–2, –4) b. quadrant iii; (2, 4) c. quadrant iii; (–2, –4) d. quadrant iv; (–4, –2)