Please help with explanations to these questions

3. The rise of MBS, mortgage-backed securities, and other somewhat complex nancial instruments is thought to be one the the primary causes behind the Global Financial Crisis and the Great Recession following the crisis. De- scribe what securitization means and the how incentives of all participants (i.e. borrowers, local banks, national banks, investment banks, insurers) led to the incredible rise of MBS in the leadup to the crisis. Hint: remember the video we watched in class. 4. Construct balance sheets for the following scenarios, then calculate both the return on investment and return on equity. 0 You start a business with $1,000 of your own money and borrow $19,000 from the bank. You buy a number of shares in a company for $20,000 and after a few good quarters, the price of the shares gain in value to $25,000. a At year end 2007, an investment bank held around $90 billion in MBS and $210 billion in other assets. The rm had equity of around $25 billion and nanced the rest of its operations with $27 5 billion in debt. By mid 2008, the value of its MBS portfolio fell to $40 billion. 0 In 2011, a worker at a tech startup in San Francisco bought a modest apartment for $1 million dollars with a mortgage where they put 35% of their own money down. Today that apartment is worth $1.7 million