The two ways of prevention of disease are-
1 general
2 specific

Prevention of diseases follows three basic principles:
1. Keeping out infectious agents, i.e. maintenance of personal and public hygiene
2. Availability of proper and sufficient food and water for everyone
3. Immunisation

For the production of honey on the commercial basis, Italian variety of honey bee, Apis mellifera is commonly used for honey production throughout the country. It is preferred because:

• It is gentle in nature.
• It has high honey collection capacity.
• It has more ability to protect itself from enemies.

Mixed cropping: This approach of growing crops involves growing two or more crops concurrently on the same land. It involves giving away some insurance against failure of one of the crops. For example, wheat and gram, wheat and mustard, sunflower and ground nut, etc.

Inter-cropping: This approach of growing crops involves growing two or more crops concurrently on the same land in a certain pattern. The crops are grown depending upon their varied nutritional requirements such that each row contain definite crops and different from the adjacent rows to ensure maximum utilization of the nutrients present in the soil. This approach also prevents the attack of pests and spread of diseases. For example, maize and soyabean, bajra and lobea, etc.

Sonar, short for Sound Navigation and Ranging, is a technique that uses propagation of  sound waves  to communicate, navigate and detect the objects on or under the surface of the water.
Working of sonar:

1. Sonar can send the sound waves towards the depth of the ocean
2. When these sound waves hit the objects like fish, vegetation or the bottom of the ocean , they are reflected back to the surface in the form of echo.
3. The sonar device measures how long it takes for the sound wave to travel down, hit an object and then bounce back up.
4. This information enables the device to to measure the depth of the object
5. And also it  measures the strength of the returning pulse  to know the  the strength of the objects.  The harder the objects, the stronger the return of the sound wave.

Global warming is the phenomenon of gradual increase in temperature near the Earth’s surface. This phenomenon has been observed over the past one or two centuries. This change has disturbed the climatic pattern of the earth. However, the concept of global warming is quite controversial. But, the scientists have provided relevant data in support of the fact that the temperature of the Earth is rising constantly.

Example of prokaryotic is Plant and Animal cell

The organelles that controls the osmotic pressure in a cell are the vacuoles, the cell has to maintain a particular pressure called the turgor pressure to maintain its shape and metabolic activities.

When a Red Blood Cell is placed in concentrated saline solution exosmosis occurs and the RBCs shrink due to excess loss of water.

Most of the plant tissues are supportive which provides them with structural strength. Most of these tissues are dead, since dead cells can provide mechanical strength as easily and need less maintenance. Animals on the other hand, move around in search of food, mates and shelter. They consume more energy as compared to plants. Most of the tissues they contain are living. Another difference between animals and plants is in the pattern of growth. The growth in plants is limited to certain regions, while in animals it is not limited to certain regions. There are some tissues in plants that divide throughout their life. These tissues are localised in certain regions. Based on the dividing capacity of the tissues, various plant tissues can be classified as growing or meristematic tissue and permanent tissue. Cell growth in animals is more uniform.

Examples of non-membrane bound organelles are ribosomes, the cell wall, and the cytoskeleton. 

Salamander are amphibian

While Lizards are reptilia

1. Reptiles (lizards) are covered in dry scales or scutes,

while Amphibians(salamander) have moist skins.

2.Amphibians(salamander) produce eggs that are dependent for the most part on water and moisture, eggs are soft and moist.

while Reptiles (lizards) have shelled-eggs that are terrestrially adapted.eggsa are hard.

3. Amphibian (salamander) They dont have claws

While Reptiles (lizards) have claws

4. Amphibians (salamander) have life stages like larval stage

While Reptiles (lizards) do not have any larval stage or life stages

 Mass of sodium carbonate = 5.3 g (given)

Mass of ethanoic acid = 6 g (given)

Mass of sodium ethanoate = 8.2 g (given)

Mass of Carbon dioxide = 2.2 g (given)

Mass of water = 0.9 g (given)

Now, total mass before the reaction = (5.3 + 6) g
= 11 . 3 g

And, total mass after the reaction = (8.2 + 2.2 + 0.9 ) g

= 11.3 g

total mass before the reaction = total mass after the reaction.

Hence, the given observations are in agreement with the law of conservation of mass.

Female Anopheles mosquitoes are the primary hosts and transmission vectors for malaria. Humans and other vertebrates are the secondary hosts.

Prevention of diseases follows three basic principles:
1. Keeping out infectious agents, i.e. maintenance of personal and public hygiene
2. Availability of proper and sufficient food and water for everyone
3. Immunisation

The weight of an object on the moon will be about one-sixth of what is on the earth. Thus, a spring balance which shows the weight of a body to be 6 N on earth will show a weight of only 1 N when taken to the moon. The weight of an object on the moon is less than that on the earth because the mass and radius of the moon are less than that of earth.

Suppose we have an object of mass m. let its weight on the moon be W_m, the mass of the moon is M_m and its radius is R_m. now, according to the universal law of gravitation, the weight of the object on the moon will be:

W_m = G x M_m x m/R_m²

Let the weight of the same object on the earth be W_e. The mass of the earth is M and its radius is R.

W_e = G x M x m/R²

W_m = G x 7.36 x 10²² kg x m / (1.74 x 10⁶ m)²

W_m = 2.431 x 10¹⁰ G x m                                                                                               i.

W_e = 1.474 x 10¹¹ G x m                                                                                                ii.

Dividing both the equations i. & ii.

W_m/W_e = 1/6

Weight of the object on the moon / Weight of the object on the earth = 1/6

Weight of the object on the moon = (1/6) × its weight on the earth.