Solve the problem.In the formula A = Iekt, A is the amount of radioactive material remaining from an initial amount I at a given time t and k is a negative constant determined by the nature of the material. A certain radioactive isotope has a half-life of approximately 1200 years. How many years would be required for a given amount of this isotope to decay to 70% of that amount?
A. 360 yr
B. 2084 yr
C. 547 yr
D. 617 yr
Answer: D
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Rewrite the quadratic function in standard form by completing the square.f(x) = x2 + 3x + 1
A. f(x) = (x + 3)3 - 9
B. f(x) = 
2 + 
C. f(x) = (x - 3)3 - 9
D. f(x) = 
2 - 
Classify the polynomial as constant, linear, quadratic, cubic, or quartic, and determine the leading term, the leading coefficient, and the degree of the polynomial.f(x) = 19x4 - 9 + 0.18x2 - 6x
A. Quadratic; 0.18x2; 0.18; 2 B. Quartic; 19x4; 19; 4 C. Quadratic; x4; 19; 4 D. Constant; -9; -9; 0
Use the information given about the angle ?, 0 ? ? ? 2?, to find the exact value of the indicated trigonometric function.tan ? = 
, ? < ? < 
Find sin 
.
A. - 
B. 
C. - 
D. 
A population of eight beavers has been introduced into a new wetlands area. Biologists estimate that the maximum population the wetlands can sustain is 60 beavers. After 3 years, the population is 15 beavers. The population follows a Gompertz growth model. How many beavers will there be in the wetlands after 10 years? ?
A. 34 beavers B. 32 beavers C. 30 beavers D. 31 beavers E. 39 beavers