Answer: v = 880m/s
Explanation: The length of a string is related to the wavelength of sound passing through the string at the fundamental frequency is given as
L = λ/2 where L = length of string and λ = wavelength.
But L = 1m
1 = λ/2
λ = 2m.
But the frequency at fundamental is 440Hz and
V = fλ
Hence
v = 440 * 2
v = 880m/s
Answer
Any force greater 490N
Explanation
The force required just to make an object slide over a rough horizontal surface is any force greater that the static friction which given by;

Given;

Hence;
F = 0.5 x 100 x 9.8
F = 490N.
We will only need the coefficient of kinetic friction if we were asked to find the force required to keep the object moving uniformly. Usually, the force needed to keep an object moving uniformly over a rough surface is lesser that which is needed to start its motion.
In this problem, we were only asked to find the minimum force required to make the object move which we have done.
<span>Audible beats are formed by the interferences of two waves in which are from the slightly different frequencies which is letter a. It is because having two waves that consist of slightly different frequency causes or produce the audible beats to be formed in which they are beats that causes sound to be either loud or soft.</span>
The answer to that I think would be D because:
A is wrong because it doesn't make sense the way the order it is in,
B doesn't make sense because it is in the wrong order, and
C says the same exact thing that photosynthesis says which would mean that it is representing the photosynthesis equation not the chemical equation for cellular respiration.
Also it is D because D shows the correct way that the chemical equation representing cellular respiration is supposed to be in.
Hope this helped!