How too work this out

Agrocery sells green apples and red apples. on monday , the store put 500 of each kind of apple on display. that day, the store sold 42 red apples and 57 green apples.on tuesday the store sold 87 red apples and 75 green apples. on wednesday, the store sold 29 red apples and 38 green apples

Suppose there is a simple index of three stocks, stock abc, stock xyz, and stock qrs. stock abc opens on day 1 with 4000 shares at $3.15 per share. stock xyz opens on day 1 with 5000 shares at $4.30 per share. stock qrs opens on day 1 with 6000 shares at $4.60 per share. the price of stock abc on day 8 begins at $3.50. the price of stock xyz on day 8 begins at $3.90. stock qrs opens on day 8 with a price of $4.50 per share. assume that each stock has the same number of shares that it opened with on day 1. what is the rate of change of this simple index over 1 week?

If sin(x) = 0 and cos(x) = 1, what is tan(x)?