Sample Response: I disagree with him because the angle of incidence is the angle between the incoming ray and the normal. The normal is perpendicular to the surface of the mirror.
this is the answer for edginuity and the other person was wrong
The FitnessGram™ Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. [beep] A single lap should be completed each time you hear this sound. [ding] Remember to run in a straight line, and run as long as possible. The second time you fail to complete a lap before the sound, your test is over. The test will begin on the word start. On your mark, get ready, start.
The half-life of carbon-14 is equal to 5730 years. The amount of substance with half-life h at any time t is equal to,
At = (Ao) x (1 - 0.5)^(t/h)
Substituting,
At/Ao = 0.67 = 0.5^(t/5730)
The value of t from the equation is 3310.6 years.