Answer:
835.29 Hz
Explanation:
When moving towards the source of sound, frequency will be given by
f*=f(vd+v)/v
Where f is the freqiency of the source, vd is the driving speed, v is the speed of sound in air, f* is the inkown frequency when moving forward.
Substituting 800 Hz for f, 340 m/s for v and 15 m/s for vd then
f*=800(15+340)/340=835.29411764704 Hz
Rounded off, the frequency is approximately 835.29 Hz
You have to make sure you know what your doing plus if you have your license and stuff to fly you have to practice on a 25 minute course
Answer:
(A) 
Explanation:
The net force perpendicular to the surface of the incline is the sum of the gravity force component, which is mgcos(theta), and the reactionary normal force caused by the surface of the incline. The sum is F_N - mgcos(theta) and is usually 0 which is why the object is not moving perpendicularly to the surface of the incline.
It seems that you have missed the necessary options for us to answer this question so I had to look for it. Anyway, the answer to the given statement is FALSE. Pigments are NOT always made of natural materials. Pigments can either be man-made or the one that occurred naturally as what you see in our environment. Hope this helps.