Explanation

The sentence expresses moral obligation, and "ought to" is suitable for that.

Correct usage: "You ought to complete your homework before you go out."

Explanation

This is a classic inverse proportion problem:
More men → Less time required.

Given:

• 10 men take 40 days

• 20 men will take ? days

Since the number of men and the number of days are inversely proportional:

$$text{Men}_1 times text{Days}_1 = text{Men}_2 times text{Days}_2$$$$10 times 40 = 20 times x$$ $$400 = 20x Rightarrow x = frac{400}{20} = 20$$

Explanation

The phrase "after the performance was over" indicates a completed action in the past.

So, the simple past tense "contacted" is correct.

Explanation

Titled "Global Climate Risk Index 2021", the report by Germanwatch was released on 25^th January 2021 and showed Pakistan drop from 5th most vulnerable country to climate change, to the 8th position.

The think-tank said it took into account most data from 2000 to 2019 to analyze and rank "to what extent the countries and regions have been affected by impacts of climate-related extreme weather event" such as storms, floods, and heatwaves.

Explanation

Explanation

√3, √4, √5 →  3+4=7 =5 Not valid

Explanation

Simplify the square root:

√1.96/100

√1.96/ √100

√1.96 = 1.4

√100 =10

14/10 = 0.14

Explanation

Criterion پہچان معیار,

Explanation

40 men finish the work in 25 days

Total work = 40 men * 25 days = 1000 man-days

Now, 25 men will finish the work:

1000 man-days / 25 men = 40 days

Explanation

We are given two equations:

Let:

• Cost of one apple = x

• Cost of one orange = y

From the problem:

1. $4x + 2y = 30$
   

2. $$x+3y=15

   
   Step 1: Solve the system of equations

Equation (1):
$4x + 2y = 30$
Divide the whole equation by 2:
→ $2x + y = 15$→ (3)

Equation (2):
$x + 3y = 15$ → (2)

Step 2: Solve equations (2) and (3)

From (3):
$y = 15 - 2x$ → (4)

Substitute (4) into (2):
$x + 3(15 - 2x) = 15$
$x + 45 - 6x = 15$
$-5x+45=15$
$-5x=15-45=-30$
$$x=−30−5=6