A sound wave produced by a loudspeaker can travel through water, but not through a vacuum. In comparison, a red light wave produced by a laser can
travel through
A. both water and a vacuum
B. a vacuum, but not through water
C. neither water nor a vacuum
D. water, but not through a vacuum
Please help

The extremely high temperatures needed to trigger nuclear fusion are proposed to be generated by laser irradiating a spherical pellet of deuterium and tritium fuel of diameter 1.8 mm. (a) determine the maximum fuel temperature that can be achieved by irradiating the pellet with 200 lasers, each producing a power of 550 w. the pellet has an absorptivity 0.3 and emissivity 0.8.

Apulley with mass mp and a radius rp is attached to the ceiling, in a gravity field of 9.81 m/s2 and rotates with no friction about its pivot.

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.