15) a
16) b
17) a
Hope this helps
I think your answer would be DDT, but don't hold me to it
Answer:
S = 16 m
Explanation:
Given that
The frequency of the water waves, f = 4 Hz
The wavelength of the water waves, λ = 2 m
The time the waves reached the shore, t = 2 s
The relation between the velocity, wavelength, and the frequency of the wave is given by the relation,
v = f λ m/s
Substituting the given values in the above equation,
v = 4 x 2
= 8 m/s
The velocity of the water waves is v = 8 m/s
The distance between the shore and boat is given by
s = v x t
= 8 x 2
= 16 m
Hence, the distance between the boat and the shore is, s = 16 m
Let's assume that Zoey ran at a constant speed. we can use the equation,
d = st
where, d = distance, s = speed, and t = time taken.
By rearranging,
s = d/t
Zoey had travelled 100 m in 20 seconds.
Hence, s = 100 m / 20 s = 5 m/s
therefore Zoey's speed at 100 m is 5 m/s
