Desmatosuchus was a crocodile relative that lived only during the triassic period. horsetails are plants that first appeared in the triassic period and still exist. which of these organisms would be more useful as an index fossil for the triassic period? why?

if you just answer this to get the points you're gonna be reported

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