How much does a gold bar weigh and how much is it worth?

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?

What’s #16 asking me and how do i solve it?

Which is not true of alpha radiation? o a. it increases the number of protons. o b. it has a positive charge. o c. it causes transmutation. o d. it is heaviest of the three types