What is 56.6666666667 in scientific notation?

Aproton is projected toward a fixed nucleus of charge +ze with velocity vo. initially the two particles are very far apart. when the proton is a distance r from the nucleus its velocity has decreased to 1/2vo. how far from the nucleus will the proton be when its velocity has dropped to 1/4vo?

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

Aria drove to the store, did some shopping, and then came home. during maria's trip, when was her displacement equal to zero?