First, before determining which variable is which, we go over the definition of each.
The independent variable is the one which is intentionally changed in order to investigate its effect on the dependent variable.
The dependent variable is monitored and changes occur in it due to the changing conditions of the independent variable.
In this case, the location of the African violets is the independent variable as it is intentionally changed, while the rate of growth of the African violets is the dependent variable as it is being measured.
The quantity that has a magnitude of zero when the ball is at the highest point in its trajectory is
the vertical velocity.
In fact, the motion of the ball consists of two separate motions:
- the horizontal motion, on the x-axis, which is a uniform motion with constant velocity

, where

- the vertical motion, on the y-axis, which is a uniformly accelerated motion with constant acceleration

directed downwards, and with initial velocity

. Due to the presence of the acceleration g on the vertical direction (pointing in the opposite direction of the initial vertical velocity), the vertical velocity of the ball decreases as it goes higher, up to a point where it becomes zero and it reverses its direction: when the vertical velocity becomes zero, the ball has reached its maximum height.
Answer:
40 MJ (D)
Explanation:
Quantity of heat (Qh) = 100 MJ
temperature of steam (Th) = 450°c = 450 + 273 = 723 K
emperature of water (TI) = 20 °c = 20 + 273 = 293 k
efficiency = (Qh-Qi)/Qh = (Th-Ti)/Th

- Qi= 0.5947 x 
- (0.5947 x
) = Qi
Qi = 40.5 MJ equivalent to 40 MJ (D)
Formula for height
<span> r(t) = a/2 t² + v₀ t + r₀
</span><span> where
</span><span> a = acceleration = -32 ft/sec² (gravity)
</span><span> v₀ = initial velocity
</span><span> r₀ = initial height
</span><span> r(t) = -16t² + v₀ t + r₀
</span> <span>Tomato passes window (height = 450 ft) after 2 seconds:
</span><span> r(2) = 450
</span><span> -16(4) + v₀ (2) + r₀ = 450
</span><span> r₀ = 450 + 64 - 2v₀
</span><span> r₀ = 514 - 2v₀
</span><span> Tomato hits the ground (height = 0 ft) after 5 seconds:
</span><span> r(5) = 0
</span><span> -16(25) + v₀ (5) + r₀ = 0
</span> r<span>₀ = 16(25) - 5v₀
</span><span> r₀ = 400 - 5v₀
</span><span>
r₀ = 514 - 2v₀ and r₀ = 400 - 5v₀
</span> <span>514 - 2v₀ = 400 - 5v₀
</span><span> 5v₀ - 2v₀ = 400 - 514
</span> <span>3v₀ = −114
</span><span> v₀ = −38
</span><span> Initial velocity = −38 ft/sec (so tomato was thrown down)
</span><span> (initial height = 590 ft) </span>