Which are uses of lasers? pick all that apply. a. scanning a bar code on a price tag for a shirt b. creating a magnified image of the moon cutting an iron bar into two pieces c. reshaping a cornea to improve vision d. making a leaf appear larger so its veins are visible

Ineed with these last two questions: 1) what are two types of cold air masses that influence the weather in north america? name them and describe their humidity. 2) describe the motion of a cold air mass and a warm air mass and the weather you would expect at a warm front and an occluded front.

Abird sitting high in a tree is an example of what type of wnergy

Modern physics a photon emitted from an excited hydrogen atom has an energy of 3.02 electron volts. which electron energy-level transition would produce this photon? a. n=1 to n=6 b. n=2 to n=6 c. n=6 to n=1 d. n=6 to n=2 i chose b but the correct answer is d can someone tell me why? and what's the difference?