43. (a) 1 mark What do you understand by an arithmetic mean, in reference to arithmetic sequences? (b) i. 1/2 mark Is it always possible to insert an arithmetic mean between any two given numbers? i. ii. 1/2 mark How many arithmetic means can be inserted between any two given numbers? iii. 1 mark Briefly describe how to insert arithmetic means between any two given numbers. 44. 2 marks Construct an example to show that the second differences of a quadratic relation in standard form (that is, y = ax2 + bx + c) always equal 2a.45. Each person's blood pressure is different, but there is a range of blood pressure values that is considered healthy. The function p(t) = 20 cos(300t) + 100 (4) models the blood pressure, p, in millimetres of mercury, at time , in seconds, of a person at rest. (a) |2 marks | What is the period of the function? What does the period represent for an individual? (b) How many times does this person's heart beat each minute? (c) Sketch the graph of p(t) within the interval 0