What is the term for the partially visible impressions that…

What is the term for the partially visible impressions that are left on the sheet of paper underneath the one on which the visible writing was done? Example: I write in a notebook, and the writing left impressions on the page underneath from the pressure of my writing 

Tammy Deitel has $10,000 and is forming a portfolio with Sto…

Tammy Deitel has $10,000 and is forming a portfolio with Stocks P and Q. [The weights of P and Q in the portfolio are both positive.] P Q Expected return, r (%) 16 23 Standard deviation, σ (%) 19 27 The standard deviation of the portfolio can be smaller than 19 if P and Q are significantly and positively correlated.