Tritium (³H) Is Used in Glowing "EXIT" Signs Located Where

question 123

Multiple Choice

Tritium (³H) is used in glowing "EXIT" signs located where there is no electricity for lightbulbs. If the half-life of tritium is 12.26 years, what percentage of the original quantity of the isotope is left in the sign after 18.5 years?

• A)0.632%
• B)63.2%
• C)35.1%
• D)1.51%
• E)25.0%

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Definitions:

Efferent Ductule

Tiny tubes that transport sperm from the testes to the epididymis in male reproductive systems.

Cowper Gland

A pair of small glands in the male reproductive system that produce a pre-ejaculate fluid which helps to lubricate the urethra for sperm to pass through.

Scrotum

The pouch of skin that hangs below the penis in males, housing the testicles and parts of the spermatic cord, playing a role in temperature regulation for sperm production.

Prostate

A gland in male mammals surrounding the neck of the bladder and urethra, involved in the production of seminal fluid.