When you observe you use one or more of your senses to

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

Aspecimen of oil having an initial volume of 580cm^3 is subjected to a pressure increase of 4.0 mpa, and the volume is found to decrease by 0.40 cm^3. (a) what is the bulk modulus of the material? (b) what is the compressibility of the material?

Could someone . i have tried to solve myself but my calculation is off