A potato gun is fired horizontally from a height of 1.5 meters with the potato launched at 25 m/s.

I don't have the full question but here

(a)

Set the height equal to gt2/2 and solve for t.

h = gt2/2

t = √(2h/g)

h = 1.5 m

g = 9.8 m/s2

Plug in the numbers and get t in seconds.

(b)

x = vxt

vx = 25 m/s

t = result from part (a)

Plug in the numbers and get x in meters.

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation: