Describe the differences between a song with high frequency and one with a deeper tone

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

10. translate each of the following chemical equations into a sentence. a. 2 zns(s) + 3 o2(g) -> 2 zno(s) + 2 so2(g) b. cah2(s) + 2 h2o(l) -> ca(oh)2 (aq) + 2 h2(g)

Which of these is a physical property