Answer:
The observer detects light of wavelength is 115 nm.
(b) is correct option
Explanation:
Given that,
Wavelength of source = 500 nm
Velocity = 0.90 c
We need to calculate the wavelength of observer
Using Doppler effect
Where, 
Hence, The observer detects light of wavelength is 115 nm.
Digestive system: consists of the gastrointestinal tract plus the accessory organs of digestion. Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body.
Endocrine system: a chemical messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs.
Eukaryotes: organisms whose cells have a nucleus enclosed within a nuclear envelope.
Excretory system: an organism's body that performs the function of excretion, the bodily process of discharging wastes.
Golgi Apparatus/complex: an organelle found in most eukaryotic cells. Part of the endomembrane system in the cytoplasm, it packages proteins into membrane-bound vesicles inside the cell before the vesicles are sent to their destination.
Lysosome: a membrane-bound cell organelle that contains digestive enzymes. They break down excess or worn-out cell parts. They may be used to destroy invading viruses and bacteria.
Mitochondria: a membrane-bound cell organelles that generate most of the chemical energy needed to power the cell's biochemical reactions.
Muscular system: an organ system consisting of skeletal, smooth and cardiac muscles. It permits movement of the body, maintains posture and circulates blood throughout the body
Nervous system: the network of nerve cells and fibers which transmits nerve impulses between parts of the body.
Nucleus: a membrane-bound organelle that contains DNA of eukaryotic organisms. As such, it serves to maintain the integrity of the cell by facilitating transcription and replication processes.
Organ: a group of tissues in a living organism that have been adapted to perform a specific function.
Organism: an individual animal, plant, or single-celled life form.
Organ system: a group of organs that work together as a biological system to perform one or more functions
Prokaryotes: a microscopic single-celled organism that has neither a distinct nucleus with a membrane nor other specialized organelles.
Ribosome: a minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.
Respiratory system: a biological system consisting of specific organs and structures used for gas exchange in animals and plants.
Rough endoplasmic reticulum: an organelle found in eukaryotic cells. Its main function is to produce proteins. It is made up of cisternae, tubules and vesicles.
Skeletal system: The human skeleton is the internal framework of the human body.
Smooth ER: is a membranous organelle found in most eukaryotic cells
Tissue: a group of cells, in close proximity, organized to perform one or more specific functions.
Vacuole: a membrane-bound organelle.
Answer:
Tension in the cable is T = 16653.32 N
Explanation:
Give data:
Cross section Area A = 1.3 m^2
Drag coefficient CD = 1.2
Velocity V = 4.3 m/s
Angle made by cable with horizontal =30 degree
Density 
Drag force FD is given as
Drag force = 14422.2 N acting opposite to the motion
As cable made angle of 30 degree with horizontal thus horizontal component is take into action to calculate drag force
TCos30 = F_D
T = 16653.32 N
