How long do certain ridges take to form?

What ribosome cellular function are they involved in? Do we exhale to remove excess oxygen from the lungs? How do you type cross? What is the relationship between radius and surface area to volume ratio How does SAV affect the interactions a substance has with its surroundings? When did mount fuji last erupt? Where can one purchase a cellular repeater? What is the connection between sunlight and ozone formation? How old is Triton? Who wrote this line 'we were in the middle of our writing lesson that mean old Gilbert Blythe was being so obnoxious that i put down my chalk and cracked my slate right over his head? What is the cleft between cerebral hemispheres? Do you have right thumb and left thumb same finger print? Ammonium Carbonate heated makes what? What is the latitude and longitude of Epidaurus the 14000 seat ampitheatre? What is cytospin? What are the carriers of current in an electrolytic solution? Can camphor and NaCl be saparated by sublimation? What type of crystal structure does the opal have? Why is the Galveston hurricane 1900 referred as the worst storm in US? What is the type of root found in dicots? How are particles of matter affected with increasing or reducing pressure on the matter at a given temperature?

How long do certain ridges take to form?