A and D, sorry if I’m wrong.
100 degrees - all angle measurements in a triangle will add up to 180 degrees (45+55 = 100, 180-100 = 80)
3/10 times 2/3 3 times 2 is 5 and 10 times 3 is 30 5/30 a
Answer:

Step-by-step explanation:
Given that the population of a city increased steadily over a ten-year span. The following ordered pairs show the population x and the year y over the ten-year span in the form (x, y) for specific recorded years.
x y
2500 2001
2650 2002
3000 2004
3500 2007
4200 2011
Slope 0.005865485
Intercept 1986.406413
So regression line is

When population = 15000

Answer:
a) 5.13beats/min
b) 2.82 beats/min
Step-by-step explanation:
Given the pulse rate of a person modelled by the equation y = 600x^-1/3 for 30≤x≤75
If the height is 39inches, the instantaneous rate of change of pulse rate for the heights will be expressed as;
y = 600(39)^-1/3
y = {600(1/39)}/3
y = 600/39×3
y = 600/117
y ≈ 5.13beats/min
The instantaneous rate for a 39 inches tall person is 5.13 beats per min
b) For a 71inches tall person, the beat rate will be expressed as;
y = 600(71)^-1/3
y = {600(1/71)}/3
y = 600/71×3
y = 600/213
y ≈ 2.82 beats per minute
The instantaneous rate for a 71 inches tall person is 2.82 beats per min