Answer:
Step-by-step explanation:
rate of change=cost per song
so the first option
Answer: C. 
Step-by-step explanation:
Given: The formula below can be used to find D, the difference in temperature between the pan and the room after t minutes.

At t= 8 minutes, we get

The approximate temperature of the pan after it has been away from the heat for 8 minutes= 
Greater than because they are negative
Infinite intervals are closed if they contain a finite endpoint, and open otherwise. The entire real line is an infinite interval that is both open and closed
The Given Triangle PMO is a Right Angled Triangle with m∠M = 90°
Given m∠P = 40°
We know that : Sum of Angles in a Triangle = 180°
⇒ m∠P + m∠M + m∠O = 180°
⇒ 40° + 90° + m∠O = 180°
⇒ 130° + m∠O = 180°
⇒ m∠O = 180° - 130°
⇒ m∠O = 50°
We can notice that m∠O and m∠1 form a Linear Pair (180°)
⇒ m∠O + m∠1 = 180°
⇒ 50° + m∠1 = 180°
⇒ m∠1 = 180° - 50°
⇒ m∠1 = 130°
Last Option is the Answer