Answer:
vertical distance, s = 0.16 meters
Explanation:
It is given that,
An amateur player is about to throw a dart with an initial velocity of 15 meters/second onto a dartboard.
Dashboard is placed at a distance of 2.7 meters.
Calculating time from velocity and distance i.e. 
Using second equation of motion for finding vertical distance :

Here, u = 0 (for vertical velocity )
s = 0.162 meters
or s = 0.16 meters
Hence, the vertical distance by which the player will miss the target if he throws the dart horizontally, in line with the dartboard is 0.16 meters.
Answer:
I₂ = 0.04 W / m²
Explanation:
Sound intensity is the power emitted between the unit area
I = W / A
W = I A
sound is a wave that travels in space whereby its energy is distributed on the surface of a sphere
A = 4π r²
we substitute
W = I (4π r²)
the emission power is constant, so the intensity at two different points is
W = I₁ 4π r₁² = I₂ 4π r₂²
so the equation is
I₁ r₁² = I₂ r₂²
In this case the units are not shown in the exercise, suppose that all units are in the SI system
I₂ =
let's calculate
I₂ = 4
I₂ = 0.04 W / m²
1. e) None of the above is necessarily true.
2.d) Without knowing the mass of the boat and the sack, we cannot tell.
The signs of a chemical reaction are bubbles, heat an magnesium disappearing.