10. The half-life of a radioactive substance is 15 years.
Write an equation that can be used to determine
the amount, s(t), of 200 grams of this substance
that remains after t years. (2 points)
Determine algebraically, to the nearest year, how
long it will take for 1/10 of this substance to
remain. (3 points)

Aheated piece of metal cools according to the function c(x) = (.5)x ? 7, where x is measured in hours. a device is added that aids in cooling according to the function h(x) = ? x ? 2. what will be the temperature of the metal after two hours?

How does reflecting or rotating a figure change the interior angles of the figure?

What is the next step in the given proof? choose the most logical approach. a. statement: m 1 + m 2 + 2(m 3) = 180° reason: angle addition b. statement: m 1 + m 3 = m 2 + m 3 reason: transitive property of equality c. statement: m 1 = m 2 reason: subtraction property of equality d. statement: m 1 + m 2 = m 2 + m 3 reason: substitution property of equality e. statement: 2(m 1) = m 2 + m 3 reason: substitution property of equality