Question Discussion & Solution

1) × and ÷

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 × 2 ­- 7 ÷ 3 + 5

= 46 × 2 ­- 2.33 + 5

= 92 ­- 2.33 + 5

= 97 -­ 2.33

= 94.67 ≠ 39

2) ­- and ×

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 × 7 -­ 3 + 5

= 23 × 7 -­ 3 + 5

= 161 ­- 3 + 5

= 166 ­- 3

= 163 ≠ 39

3) + and ×

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 7 + 3 × 5

= 23 ­- 7 + 3 × 5

= 23 ­- 7 + 15

= 38 7

= 31 ≠ 39

4) + and ­-

Given statement: 46 ÷ 2 -­ 7 × 3 + 5 = 39

On interchanging the above signs,

46 ÷ 2 + 7 × 3 ­- 5

= 23 + 7 × 3 ­- 5

= 23 + 21 ­- 5

= 44 -­ 5

= 39

Hence, “21” will come next.

Concept:

Latent heat: It is the amount of heat needed to change the state of a unit mass of any substance without changing its temperature.

i.e., we can say that heat needed to supply for changing its state will be directly proportional to the mass m of the substance.

∴Q ∝ m

i.e.,Q = mL

The SI unit of Latent heat is J/Kg and the CGS unit is Cal/g respectively.

Where,

m = mass of an object

L = Latent heat

Q = amount of heat needed to change the state of matter of mass m 

Explanation:

From the above explanation, we can see that Amount of heat needed to melt a unit mass of a substance is directly proportional to the amount of mass of an object since the Latent heat of a material is constant.

i.e., Q ∝ m ⇒ Q = mL

Thus the unit of latent heat can be expressed as \(L=\frac{Q}{m}\Rightarrow L=\frac{Joules}{kg}\)

The correct answer is the save as.

• Using the F12 key in MS Word, Save as dialogue box opens​.

​Key Points

• F12 key used with other keys in MS word:​.
  • Ctrl+F12 
    • ​Opens a document in Word.
  • Shift+F12 
    • Saves the Microsoft Word document (like Ctrl+S).
  • Ctrl+Shift+F12
    • Prints a document in Microsoft Word.

Additional Information

• Keys for performing a mail merge
  • Preview a mail merge
    • ​ALT + SHIFT + K
  • ​Merge a document
    • ​ALT + SHIFT + N
• ​Insert Table
  • ​To open the Insert tab to insert tables, pictures, and shapes, headers, or text boxes.
    • Alt+N
• Insert Picture
  • ​The shortcut key to import a picture is Ctri+G

The pattern followed is