Use Sinclair’s work to answer the questions and complete the statements. How did Sinclair come up with the dimensions 1, 7 3 , and 5 3 in step 2? He multiplied the original dimensions by a scale factor of . What can Sinclair conclude about the effect on the trapezoid’s area from his comparison? The changes created an area times the original area.

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60

Consider a cube that has sides of length l. now consider putting the largest sphere you can inside this cube without any point on the sphere lying outside of the cube. the volume ratio -volume of the sphere/ volume of the cube is 1. 5.2 × 10−1 2. 3.8 × 10−1 3. 1.9 4. 2.5 × 10−1 5. 3.8

00 points ! missy’s rotation maps point k(17, –12) to k’(12, 17). which describes the rotation? 270° counterclockwise rotation 90° counterclockwise rotation 90° clockwise rotation 180° rotation