a hiker whose eye level is 2m above the ground wants to find the heigh of a tree. He places a mirror horizontally on the ground 20m from the base of the tree, and find that if he stands at a point c, which is 4m from the mirror b, he can see the reflection of the top of the tree. How tall is the tree

Klein read 30 pages of a book on monday and 1/8 of the book on tuesday. he completed the remaining 1/4 of the book on wendesday. how many pages are there in the book?

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?

What expression is equivalent to 42x-56y