Which of the following atomic numbers represent an element that is radioactive on the periodic table.

1. N=11
2.N=56
3.N=81
4.N=100

Amachinist needs to remove a tight fitting pin of material a from a hole in a block made of material b. the machinist heats both the pin and the block to the same high temperature and removes the pin easily. what statement relates the coefficient of thermal expansion of material a to that of material b? a) the situation is not possible, heating block b will shrink the hole in the material as the material expands with increasing temperatureb) material b has the same coefficient of expansion as does material ac) material b has a negative coefficient of expansion and a has a positive coefficient of expansiond) material a has a greater coefficient of expansion than does material be) material b has a greate

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Transfer chemicals from one location to another to weather objects. a-water b-physical weathering c-chemical weathering