The hourly temperature at Portland, Oregon, on a particular day is recorded below. 1 A. M.

2

3

4

5

6

7

8

9

10

11

12 Noon

46°

44°

43°

41°

40°

40°

41°

43°

46°

52°

65°

69°

1 P. M.

2

3

4

5

6

7

8

9

10

11

12 Midnight

72°

74°

75°

75°

77°

75°

74°

70°

62°

55°

51°

48°

a. Find the amplitude of a sinusoidal function that models this temperature variation.

b. Find the vertical shift of a sinusoidal function that models this temperature variation.
c. What is the period of a sinusoidal function that models this temperature variation?
d. Use t = 0 at 5 P. M. to write a sinusoidal function that models this temp. variation.
e. What is the model’s temperature at 10 A. M.? Compare this to the actual value?

Simonne used the following steps to simplify the given expression. 12 - 3(-2x + 4) step 1: 12 + (–3)·(–2x) + (–3)·(4) step 2: 12 + 6x + (–12) step 3: 12 + (–12) + 6x step 4: 0 + 6x step 5: 6x what property of real numbers was used to transition from step 3 to step 4? a. identity property of addition b. inverse property of addition c. associative property of addition d. commutative property of addition

Jose predicted that he would sell 48 umbrellas. he actually sold 72 umbrellas. what are the values of a and b in the table below? round to the nearest tenth if necessary

Since opening night, attendance at play a has increased steadily, while attendance at play b first rose and then fell. equations modeling the daily attendance y at each play are shown below, where x is the number of days since opening night. on what day(s) was the attendance the same at both plays? what was the attendance? play a: y = 8x + 191 play b: y = -x^2 + 26x + 126 a. the attendance was never the same at both plays. b. the attendance was the same on day 5. the attendance was 231 at both plays on that day. c. the attendance was the same on day 13. the attendance was 295 at both plays on that day. d. the attendance was the same on days 5 and 13. the attendance at both plays on those days was 231 and 295 respectively.