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Answer: A good night’s sleep is usually 7-9 hours long, varying by age and maturation. Preparing for a good night’s sleep should include limiting caffeine, avoiding big meals, avoiding alcohol, and avoiding eye-strain before sleeping.
Habits that prevent a good night’s include [everything said not to do listed in the above paragraph].
Answer: 4 This group of substances can produce chemical vapors that can be inhaled to produce a mind-altering effect.
stimulants
psychoactives
inhalants
depressants
Answer: Fitness is the condition of being physically fit and healthy and involves attributes that include, but are not limited to mental acuity, cardiorespiratory endurance, muscular strength, muscular endurance, body composition, and flexibility.
Short answer:
Valve which permits blood to flow from the right atrium to the right ventricle is tricuspid valve
Long answer:
The right side of the heart has lower pressure compare to the left side. There is a valve that support the lower pressure so the blood can move easily from the right atrium to the left ventricle. The valve is called tricuspid valve. It's called "Tri" because there are 3 flaps/leaflets on the valve.
For your information, the left side of the heart only has 2-leaflet valve, which make smaller circular opening compare to the 3-leaflet valve on the right side. That's because the left side has higher pressure than the right side.
