Find the exact value of the expression.cos 20° cos 40° - sin 20° sin 40°
A. 
B. 
C. 
D. 
Answer: C
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Provide an appropriate response.A ______ represents money that is borrowed (or taken from savings) during a single year.
A. deduction B. debt C. deficit D. None of the above
Find the exact value of the expression.cot-1 
A. 
B. 
C. 
D. 
Use the Half-angle Formulas to find the exact value of the trigonometric function. sin 75°
A. - 
B. 
C. - 
D. 
What type of development focuses on the ways in which enduring characteristics that differentiate one person from another change over the life span?
A. cognitive B. physical C. personality D. social