Acosine function has a period of 3, a maximum value of 20, and a minimum value of 0. the function is a reflection of its parent function over the x-axis.

which function could be the function described?

f(x)=−10cos(2π3x)+10

f(x)=−10cos(3x)+10

f(x)=10cos(2π3x)+10

f(x)=10cos(3x)−10

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.