Why aren't convenience samples representative of the population?
a) the people who are hard to reach will not be represented.
b) the people who are hard to reach are probably the same as the people that are easy to reach.
c) the people who are hard to reach will be the only ones that are represented.
d) the people who are easy to reach will not be represented.

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?

Simplify the expression 10/11(22z) + (a+5) -1

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.