The answer for question 2 i guess it’s c
No. A substance floats or sinks in another substance because of
the densities of both of them.
If the density of the substance is more than the density of the other
one, it will sink. If less than the density of the other one, it will float.
is one of these the question
42) The sailboat travels east with velocity

, while the current moves south with speed

. Since the two velocities are perpendicular to each other, he resultant velocity will be given by the Pytagorean theorem:

and the direction is in between the two original directions, therefore south-east. So, the correct answer is
D) 42 mph southeast
43) Since the light moves by uniform motion, we can calculate the distance corresponding to one light year by using the basic relationship between velocity, space and time. In fact, we know the velocity:

and the time is one year, corresponding to:

therefore, the distance corresponding to one light year is:

Therefore, the correct answer is D.
44) For the purpose of the problem, we can assume that the light travels instantaneously from the flash to us (because the distances involved are very small), so the time between the flash and the thunder corresponds to the time it took for the sound to travel to us.
The speed of sound is

And since the time between the flash and the thunder is t=3 s, the distance is

Therefore, the correct answer is A) 3/5 mile.
Answer:
If a pitch vibrates at 880 cycles, the octave below would vibrate at 440 cycles.
Explanation:
Pitch of sound is defined as relative highest and the lowest point of sound. The pitch is dependent on frequency of vibration.
Octave is defined as a tone which is formed due to merging of two different tone. The resultant tone is merged so well that it sound like a single tone.
Thus, Number cycle in octave = 
Number cycle in octave = 
Number cycle in octave = 440
Thus, If a pitch vibrates at 880 cycles, the octave below would vibrate at 440 cycles.