Question 3 of 25 Which two explanations are based on personal beliefs?
D A Data gathered during experiments show that there is an inverse
relationship between the force of gravity and distance.
B. Certain mineral crystals have properties that help protect the
body from illness.
C. Medical data gathered over many years show that lack of
adequate sleep causes health problems.
D. A constellatioris position in the night sky can be used to predict
events in a person's life.
O E Observations using microscopes reveal that all known organisms
are composed of tiny structures called cells.

Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. so it is no surprise that such clothing has largely replaced thickand heavy old-fashioned coats. (a) consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 w/m·°c) with 1.5-mm-thick air space (k = 0.026 w/m·°c) between the layers. assuming the inner surface temperature of the jacket to be 28°c and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°c and the heat transfer coefficient at the outer surface is 25 w/m2·°c. (b) what would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? what should be the thickness of a wool fabric (k = 0.035 w/m·°c) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket?