What are earths two main motions called

The intensity, or loudness, of a sound can be measured in decibels (db), according to the equation , where i is the intensity of a given sound and is the threshold of hearing intensity. what is the intensity, in decibels, [i(db)], when ? use a calculator. round to the nearest whole number. 8 9 19 80

What is the earliest point in the universe that we can observe? why can’t we see back further than this?

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds