Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
Just search up how much the weight is equal to another, then multiply it, thats what i do lol sorry if im no help
A. the height of the cactus plants
Explanation:
The dependent variable in this experiment designed to test this hypothesis is the height of the cactus plants.
In a hypothesis statement, we can always deduce the dependent and independent variables.
- Independent variables do not rely on other variables. They are usually the cause of the phenomenon observed in an experiment. In this experiment, it is the rainfall on the cactus plant.
- Dependent variable is that variable that relies on the independent variable. It is usually the effect of changes in independent variable.
- The height of the cactus plant depends on the amount of rainfall in an area.
learn more:
Controlled experiment brainly.com/question/1621519
#learnwithBrainly
thermal contact
When heat flows from one object or substance to another it is in contact with, the objects or substances are said to be in thermal contact. The state where objects in thermal contact with each other reach the same temperature, no heat flows between them.
Answer:
because mercury has low melting point
Explanation:
