Una botella de masa 20 kg esta ubicada a una altura de 20 metros (calcular energía potencial )

How many seconds does it take a pebble released from rest off a bridge to fall 29.4 m ? what is the pebble's speed when it has fallen 29.4 m ?

Select the word from the list that best fits the definition classification of most stars on the h-r diagram

If an atom contains 11 protons in its nucleus, predict the element with the atomic number and electronic configuration. will the number of electrons remain the same during the chemical reaction in such an atom? explain.