Which reaction is a single replacement reaction?
2h2 + o2 → 2h2o
2h2o2 → 2h2o + o2
koh + hcl → kcl + h2o
cu + 2agno3 → 2ag + cu(no3)2

2pos suppose an object in free fall is dropped from a building. its starting velocity is 0 m/s. ignoring the effects of air resistance, what is the speed (in m/s) of the object after falling 3 seconds? give your answer as a positive decimal without units. answer here

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this

What is the empirical formula of c6h18o3? ch3o c2h5o c2h6o c2h5o5