Answer:
wavelength decreases and frequency increase
Explanation:
the higher the wavelength the smaller the frequency , the smaller the wavelength the higher the frequency
X rays because to see your bones
Answer:
The most likely items to be used are;
Ultrasound and X-rays
Explanation:
A routine visit to a dentist consists of two areas of activities, including;
a) Dental examination and check up
b) Oral prophylaxis, and dental cleaning
The dental examination may involve the use of X-rays, which allow the detection of cavities between the teeth
The dental cleaning can be carried out with the use of an ultrasound cleaner, which allow the cleaning of sensitive teeth without hurting the patient
Therefore, the items most likely to be used during a routine dental visit are ultrasound and X-rays
As we know that range of the projectile motion is given by

here we know that range will be same for two different angles
so here we can say the two angle must be complementary angles
so the two angles must be

so it is given that one of the projection angle is 75 degree
so other angle for same range must be 90 - 75 = 15 degree
so other projection angle must be 15 degree
I think it’s C. But I’m not completely sure.