Answer:
42.11 years old
Explanation:
Given that:
In 2000, a 20-year-old astronaut left Earth to explore the galaxy; her spaceship travels at 2.5 x 10^8 m/s. She returns in 2040
To find her age we use:

Δtm is time interval for the observer stationary relative to the sequence of
events = 2040 - 2000 = 40 years
Δts is is the time interval for an observer moving with a speed v relative to the sequence of event
v = velocity = 2.5 x 10^8 m/s
c = speed of light = 3 x 10^8 m/s

Here age in 2000 is 20 year, therefore when she appear she would be 20 year + 22.11 year = 42.11 years old
Answer:
C. Tension
Explanation:
The tension in the cord occurs because of the muscle power of Daryl, who lifts the brick. While doing so, Daryl needs to overcome the gravitational pull on the brick.
EXTRA:
If the brick was much heavier, than Daryl's muscles would not be able to overcome the the gravitational pull on that brick, and then the much heavier brick would remain stationary on the ground, despite the efforts made by Daryl.
3. Coal burning
The coal releases chemicals when it is burned. So it is chemical to thermal.
Answer:
Average force, F = 562.5 N
Explanation:
Mass of the golf ball, m = 0.045 kg
Initially, it is at rest, u = 0
Final speed of the ball, v = 25 m/s
The club and the ball are in contact for, 
We need to find the average force acting on the ball. It can be calculated using the formula as :


F = 562.5 N
So, the average force acting on the ball is 562.5 N. Hence, this is the required solution.
La longitud del faldón de la rampa es de 5.4 m.
La pendiente expresada en porcentaje sigue la siguiente ecuación:
(1)
Donde:
- y es la elevacion de la rampa (faldón)
- x es la longitud de la ramapa (20 m)
Sabemos que la pendiente es de 27%. Por lo tanto, usando la ecuación 1, despejamos y.


La longitud del faldón es 5.4 m
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brainly.com/question/8906330