What happens to the speed of sound when the temperature of air decreases

You notice a very one-dimensional-thinking snail crawling along one rail of a railroad track. naturally, you remove it to a safer place. but before you do, you observe it as it moves from position xi = -92.9 cm to position xf = -64.9 cm along the rail, as measured from a point where one rail abuts the next. what is the snail\'s displacement δx in centimeters?

Infrared rays have a shorter wavelength than question 11 options: x-rays. ultraviolet rays. radio waves. gamma rays.

It is really hard for me right know