How to balance the equation HNO3 + Ca(OH)2 --> Ca(NO3)2 + H20

The crust of earth may a- continets and ocean floors. b-continents only. c-layers of sedimentary rocks and continents. d-all of the above

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

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.