C. <span>When water in a lake freezes, it floats, providing insulation for organisms below.
This </span> best describes an effect of the low density of frozen water in a lake.
When applying rigid-body mechanics to the study of human beings, the assumption made is Option B.The body does not deform by bending, stretching, or compressing.
<u>Explanation</u>:
Rigid body mechanics is a body in which the gap between any two points will be constant in time, despite of external forces. The body cannot be deformed at any circumstances be it under application of any force. The forces acting over the body gets divided into two groups one is external, which shows the action of different bodies on the rigid body under force and internal force that binds the body together making it rigid. Body changes its motion only in case of pull against some external object.
B. Break down dead organisms
Fungi are decomposers. they breakdown the bodies of dead organisms. They play a very important role.
1 .insecta
2.arachnida
3. bryophyta
4. mollusca
5. mammalia
6. aves
<u>Explanation:</u>
six legs and three body parts- insecta
2.eight legs and two body parts- arachnida
3. non-vascular and reproduces by spores- bryophyta
4. soft bodies with hard shells- mollusca
5. give birth to live young ones- mammalia
6. lays eggs on land and flies- aves