Find the value of each variable. For the​ circle, the dot represents the center. A four sided polygon is inside a circle such that each vertex of the polygon is a point on the circle. The top and bottom sides of the polygon slowly rise from left to right. The left and right sides of the polygon quickly fall from left to right. The angle measures of the polygon are as follows, clockwise from the top left: "c" degrees, 123 degrees, 92 degrees, and "d" degrees. The arc bounded by the left side of the polygon is labeled 94 degrees. The arc bounded by the right side of the polygon is labeled "b" degrees. The arc bounded by the bottom side of the polygon is labeled "a" degrees.

123 degrees

92 degrees

94 degrees

c degrees

d degrees

b degrees

a degrees

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