Answer:
63 degrees
Step-by-step explanation:
(180-54)/2=126/2=63
28x+-21 you simplify them first
A stuntman jumping off a 20-m-high building is modeled by the equation h = 20 – 5t2, where t is the time in seconds. A high-speed camera is ready to film him between 15 m and 10 m above the ground. For which interval of time should the camera film him?
Answer:

Step-by-step explanation:
Given:
A stuntman jumping off a 20-m-high building is modeled by the equation
-----------(1)
A high-speed camera is ready to making film between 15 m and 10 m above the ground
when the stuntman is 15m above the ground.
height
Put height value in equation 1





We know that the time is always positive, therefore 
when the stuntman is 10m above the ground.
height
Put height value in equation 1







Therefore ,time interval of camera film him is 
Total Time = (M x K) / (M + K)
5 = (8 x K) / (8 + K)
40 + 5 K = 8K
40 = 3K
King can do the job in 13.33 Hours
King could mow (1 / 13.33) of the lawn in one hour.
The length of the circle's radius = 744.92 cm
Given the length of arc of a circle, arc length = 269π cm
Central angle of a circle is the angle made between the radius through the arc length at the center of the circle.
The corresponding central angle = 65°
To find the corresponding central angle in radians = 65° x π/180 = 13π/36 radians
We have, arc length of a circle = radius x central angle
Therefore, radius of the circle = arc length / central angle
= 269π /(13π/36)
= 744.92 cm
Learn more about arc length of a circle at brainly.com/question/28108430
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