The modulating signal m(t) = 2 cos 4000πt + 4 cos 6000πt is multiplied by the carrier c(t) = 100 cos 2πfct, where fc = 50 kHz. Determine and sketch the spectrum of the DSB signal.

Spend time observing or thinking about events that involve matter and energy. which events can you explain? which events can’t you explain?

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix.b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds.c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer.d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.