Although the semi truck certainly has a larger mass, it is not in motion and therefore does not have any momentum. The bicycle however has both mass and velocity and therefore has the larger momentum of the pair.
A heterogeneous mixture is a mixture that contains two or more distinct substances that you can see. You can see the different part if a heterogeneous mixture. An example of this is a salad. You can see all of the parts.
A homogeneous mixture is a mixture that is uniform and you cannot see the different parts. It is still a mixture though. An example of that would be salt water. The water and salt are not chemically combined but you cannot see the salt AND water. It is just one solution.
b is the answer there you go if you need the answer
Answer:
a) 
b) 
Explanation:
Given:
String vibrates transversely fourth dynamic, thus n = 4
mass of the string, m = 13.7 g = 13.7 × 10⁻¹³ kg
Tension in the string, T = 8.39 N
Length of the string, L = 1.87 m
a) we know

where,
= wavelength
on substituting the values, we get

or

b) Speed of the wave (v) in the string is given as:

also,

equating both the formula for 'v' we get,

on substituting the values, we get

or

or
