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 
Answer:
4 hours
Step-by-step explanation:
25 * 8 = 200
so, 30 * 8 = 240(minutes)
240 / 60 = 4 hours
Hope it helps!
Mark brianliest if I'm right please!
Answer:
The area of the circle is 379.94 mm²
Step-by-step explanation:
To solve this problem we need to use the area formula of a circle:
a = area
r = radius = 11 mm
π = 3.14
a = π * r²
we replace with the known values
a = 3.14 * (11 mm)²
a = 3.14 * 121 mm²
a = 379.94 mm²
Round to the nearest tenth
a = 379.94 mm² = 379.9 mm²
The area of the circle is 379.9 mm²
We can model this situation with an arithmetic series.
we have to find the number of all the seats, so we need to sum up the number of seats in all of the 22 rows.
1st row: 23
2nd row: 27
3rd row: 31
Notice how we are adding 4 each time.
So we have an arithmetic series with a first term of 23 and a common difference of 4.
We need to find the total number of seats. To do this, we use the formula for the sum of an arithmetic series (first n terms):
Sₙ = (n/2)(t₁ + tₙ)
where n is the term numbers, t₁ is the first term, tₙ is the nth term
We want to sum up to 22 terms, so we need to find the 22nd term
Formula for general term of an arithmetic sequence:
tₙ = t₁ + (n-1)d,
where t1 is the first term, n is the term number, d is the common difference. Since first term is 23 and common difference is 4, the general term for this situation is
tₙ = 23 + (n-1)(4)
The 22nd term, which is the 22nd row, is
t₂₂ = 23 + (22-1)(4) = 107
There are 107 seats in the 22nd row.
So we use the sum formula to find the total number of seats:
S₂₂ = (22/2)(23 + 107) = 1430 seats
Total of 1430 seats.
If all the seats are taken, then the total sale profit is
1430 * $29.99 = $42885.70
Answer:
<h3>B. m∠R = 110°, m∠T = 110°, m∠U = 70°</h3>
Step-by-step explanation:
The opposite angles of the parallelogram are the same.
From the diagram;
<S = <U and <R = <T
Given
<S = 70°
Since <S = <U, hence <U = 70°
Since the sum of angles in a quadrilateral is 360 degrees, hence;
<R+<S+<T+<U = 360
Since <R = <T, then;
<Y+<S+<T+<U = 360
2<T + 70+70 = 360
2<T = 360-140
2<T = 220
<T = 220/2
<T = 110°
Since <T = <R, then < R = 110°
Hence m∠R = 110°, m∠T = 110°, m∠U = 70°. Option B is correct