1 "yield to maturity equals market interest rate" can be regarded as being established under the assumption of strong efficient market. Usually, when we do theoretical analysis and calculate the net present value, we sometimes simplify it to the equivalence of the two. Just like we sometimes regard the interest rate of government bonds and bank interest rates as risk-free interest rates, although they are not equal. It should be said that at some point, everyone reached a tacit understanding.

Question 2 explicitly mentions coupon interest and market interest rate, so when you ask for discount, the discount factor should use its real market interest rate. The discount price in the second year can be calculated as follows: the interest income in the second year is1000 *10% =1$10, and the discount is1(1+20%) = $

Maturity refers to the time from when you hold it to when you finally repay the principal and interest, and you may sell it before maturity because of the change of the bond market price, so the time when you own it is the holding period. It seems that the book you read is more rigorous. Usually, everyone just emphasizes that the market interest rate rises and the bond price falls (the discounted present value falls). I don't think it is necessary to spend too much energy on this. It will be great to focus on understanding McGill's five bond pricing theories.