I need an explanation of a light year?

What structures of an electron microscope are comparable to the following requirements for the light microscope: (a) light waves, (b) lenses, (c) viewer's eye, (d) mirror or light source?

What processes can change sedimentary rock into metamorphic rock? A. Subduction and high pressure B. Erosion and lithification C. Heating and cooling D. Uplift and erosion

All genetic differences aong organisms originate as some kind of Mutation Polypeptide DNA Gene

What is formed when the chromosomes from an egg and sperm come together? a haploid zygote a diploid zygote a fused zygote a placental zygote

The bglF transcript is known to have a short half-life within the cytosol. What mechanism is most likely responsible for transport of this transcript to the cytoplasmic membrane once it is synthesized

Why is fresh water a limited resource? Groundwater is too difficult to access Most water covering Earth is salt water. The supply of water on Earth decreases over time. Too much water is wasted on irrigation

Which sentences describe the differences between photosynthesis and cellular respiration

Compared to most other substances, a great deal of heat is needed to raise the temperature of water by a given amount. This is because water A. is an acid. B. readily forms solutions. C. acts as a buffer. D. has a high specific heat capacity.

Question 1 What is used to classify the layers of the atmosphere? A Differences among temperature altitude, and weather B Differences among altitude, wind speed, and weather C Differences among temperature, air pressure, and density D How far away

Which had the greatest impact on the temperature the Earth's atmospher?