Which two bases pair with each other?

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

Ineed in question 5and6 in science the subject is science

Aresearcher wants to experiment with an element that reacts like phosphorus (p) but has a greater atomic mass. which element should the researcher select for the experiment?