Answer:
D wavelength
Explanation:
The different wavelengths determine the color.
Answer:

Explanation:

Round to three significant digits

Knowing the initial velocity and angle, the horizontal range formula is given by R= V^2sin(2teta) / g, so we can get
sin(2teta)=Rg/V^2
sin(2teta)= (180 x 9.8)/ 80^2= 0.27, sin(2teta)=0.27, 2teta=arcsin(0.27)=15.66, so teta=15.66/2
teta=7.83°