Explanation

Petroleum has the highest energy density among fossil fuels, making it the richest source of energy.

It is widely used in transportation, industry, and power generation due to its high calorific value.

Explanation

Factors of 70: 1, 2, 5, 7, 10, 14, 35, 70

Factors of 42: 1, 2, 3, 6, 7, 14, 21, 42

Factors of 28: 1, 2, 4, 7, 14, 28

Common factors: 1, 2, 7, 14 → Highest is 14

So, HCF = 14.

Explanation

The correct phrase is: "There is no substitute for hard work."

"Substitute" means a replacement, and the sentence implies hard work cannot be replaced.

Explanation

Normal fasting glucose concentration in blood plasma is ~70–100 mg/dL.

It translates to ~0.1% (100 mg/dL = 0.1 g/dL = 0.1%).

Explanation

Polio primarily affects the nervous system and can cause muscle weakness or paralysis.

It often targets children and may lead to permanent disability.

Explanation

To convert 45 to binary:

45 ÷ 2 = 22 remainder 1

22 ÷ 2 = 11 remainder 0

11 ÷ 2 = 5 remainder 1

5 ÷ 2 = 2 remainder 1

2 ÷ 2 = 1 remainder 0

1 ÷ 2 = 0 remainder 1

Reading remainders from bottom to top: 101101

Therefore, 45 in binary = 101101.

Explanation

Let's denote the two integers as x and y, where x > y:

Given x - y = 3 and x² + y² = 89.

From x - y = 3, we get x = y + 3.

Substitute x in the second equation:

(y + 3)² + y² = 89

y² + 6y + 9 + y² = 89

2y² + 6y - 80 = 0

y² + 3y - 40 = 0

(y + 8)(y - 5) = 0

y = -8 (not possible since y is positive) or y = 5.

If y = 5, then x = y + 3 = 8.

Check: 8² + 5² = 64 + 25 = 89.

The integers are 8 and 5.

Explanation

The phrase “got bored with the book” is a natural and grammatically correct expression.

It indicates that you lost interest in the book quickly.

Explanation

"Kind" is the correct adjective to describe someone's behavior or nature.

Kind means قسم، مہربان

Explanation

"Expand on" means to provide more details or explanation about something.

It fits contextually as you're asking someone to elaborate on their ideas.