Why is all of geologic time before the Cambrian Period sometimes collectively lumped together and called the “Precambrian"?

What is a carrier wave and how does it affect what you hear on the radio

Which of the following is not a transverse wave? a) soundb) lightc) radiod) all of thesee) none of these

The california mussel (mytilus californianus) attaches itself to a rock or other solid surface with a bundle of filaments known as the byssus. imagine that 15.0 j of work is done to stretch the distal end of the byssus. it releases 10.8 j of thermal energy as it relaxes. what is the resilience of the distal end of the byssus?