What is the mass of a 7.91cm3 piece of lead having a density of 11.34g/cm3

If this sedimentary rock layer is truly the oldest one of marine origin, what do you think that tells usabout the formation of earth's oceans?

Beaker a contains 100 ml of 1.5 mammonia. beaker b contains 100 ml of 0.50m ammonia. how does the solution in beaker a compare to the solution in beaker b?

During which of the following phases of the moon do we see the left half of the moon as lit? full moon first quarter moon gibbous moon third quarter moon any is greatly : )