You will need a periodic table to help you answer this problem. The atomic numbers are arrange from lowest to highest in the periodic table. You can locate element number 55 to be Cesium with an atomic weight of 132.905 amu. So, you start from element 56. The following elements are:
56 Barium 137.328 amu
57 Lanthanium 138.905 amu
58 Cerium 140.116 amu
59 <span>Praseodymium 140.908 amu
60 Neodymium 144.243 amu
Neodymium is already greater than 144 amu. Therefore, these elements only include Barium, Lanthanium, Cerium and Praseodymium.</span>
Answer:
D
Explanation:
It is D because once youve put together the ingredients and baked it you can not go in and taake out every ingredient and put it back to how it was before (Please also try to help me with my question it it about scaled copies, Please and thank you!)
1. when the ball is just starting to fall, it has high potential but low kinetic energy. when it hits the floor, it has high kinetic but low potential energy
2. heat energy
3. reflective-transparent would be best, as they can reflect some light while let other light through, reflective-opaque would be useless in any circumstances because no light at all would be able to get through
