Answer:A
Explanation: because The nucleus directs all of the cell's activities, including reproduction.
Answer:
Metal
Explanation:
In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal chemical element. An alkali also can be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0.
Answer:

Explanation:
The formula for efficiency is

Data:
Useful energy = 3 J
Energy input = 30 J
Calculation:

Answer: Neutral Value
Explanation: pH of the blood is maintained at 7.0 to 7.5that is neutral value.
This is because if the pH of the is lower than the maintained value then it will become acidic .
Acidic pH can cause the medical urgency known as acidosis leading to vomiting, diarrhea etc.
If the pH becomes higher, then the blood will become basic in nature and it can also leas to the death of the person.
That is why the pH of the blood is maintianed at neutral value of 7.0 to 7.5
Answer:
V = 6.17 L
Explanation:
Given data:
Volume = ?
Number of moles = 0.382 mol
Pressure = 1.50 atm
Temperature = 295 k
R = 0.0821 L. atm. /mol. k
Solution:
According to ideal gas equation:
PV= nRT
V = nRT/P
V = 0.382 mol × 0.0821 L. atm. /mol. k ×295 k / 1.50 atm
V = 9.252 L. atm. / 1.50 atm
V = 6.17 L