Hydrogen and oxygen react to form water. AT an atomic level, how do we know that a chemical reaction has occurred?

Which codon is the code for the amino acid histidine (his)?

Study the diagram of a cell. which structure is found only in plant cells and functions in the process of photosynthesis? w x y z

The table presents the average day and night temperatures in five cities. it also reveals whether a city receives substantial rainfall (wet climate) or little rainfall (dry climate). which city’s rocks are likeliest to experience frost wedging, and why? a) city a because the consistently subzero temperature would prevent water from melting b) city b because it is a wet region and the temperature fluctuates around the freezing point c) city c because it receives plenty of rain fall and the weather is moderately cool d) city d because the hot and dry weather would cause rocks to absorb water