macroeconomics: Practice with Compounding Interest and Exchange Rates

Let's suppose that you and your friends are planning on making a trip to Thailand in thirteen months (basically at the end of year) and the trip will cost each one of you $10,000, to be paid just before making the trip. Moreover, from the job you have, you get paid $6,000 each month and the interest rate on your bank's savings account is 4%(0.04), compounded monthly, such that the account is free to open with no monthly fee. Given this information, what percent (proportion) of your monthly pay check will you have to save in order to make the trip with your friends? Work through this problem carefully and show all work. Continuing with the problem setup in [1], let's suppose you are committed to making the trip to Thailand with your friends and you have just been paid by your employer. You are ready to begin putting money into your new savings account to finance the trip's cost, when you get a call from your friend who is the lead organiser of the trip. Your friend informs you that she made a mistake when calculating the trip's cost and that the correct cost is 250,000 Thai Bahts (Thailand's currency). Given that the price of a Thai Baht (THB) in terms of US dollars (USD) is eTHBUSD=1THB0.029USD, what percent (proportion) of your monthly pay check will you have to save now in order to make the trip