People are able to hear footsteps because the sound made by a foot hitting the floor travels through the air to reach their ears. is this absorption or transmission

Microscopes are often equipped with blue filters. give a reason for using blue light in a microscope

Two circles are drawn in a 12-inch by 14-inch rectangle. Each circle has a diameter of 6 inches. If the circles do not extend beyond the rectangular region, what is the greatest possible distance (in inches) between the centers of the two circles?

What occurs in a nuclear bombardment reaction?

Which of the following phenomena provides evidence of electric fields in the atmosphere? a.) lightning b.) clouds c.) rainbows d.) wind

What is the speed of a person walking 7mi in 2hours

During a medical condition screening lung capacity testing is a standard procedure. True of false

Which of the following is a unit of energy found in food? a). vitamin b) calorie c) nutrient d) water

As one goes from left to right in a period, which of the following is true? A. The number of protons decreases. B. The number of valence electrons increases. C. both A and B D. none of the above

Which of the following surfaces reflects the most light A yellow cloth B. tree trunk C aluminum foil D. Concrete sidewalk

Which part of an atom has a mass approximately equal to 1/2000 of the mass of a common hydrogen atom? A. nucleus B. electron C. proton D. electron cloud