Explanation

At 170°C, ethanol undergoes acid-catalyzed dehydration to form ethene (C₂H₄).

Concentrated H₂SO₄ acts as a dehydrating agent, removing water from ethanol.

Explanation

Maltose is made of two glucose molecules, so both structural units are the same.

Lactose = glucose + galactose (different units).

Sucrose = glucose + fructose (different units).

Explanation

Absorbance (A) is a logarithmic ratio of incident to transmitted light; hence, it is unitless.

In the Beer-Lambert law:

A=ε⋅C⋅L, only ε (molar absorptivity) carries units to balance the equation.

Explanation

Secondary syphilis commonly presents with fever, skin rashes (especially on palms and soles), and joint pain.

It occurs weeks after the primary sore and indicates systemic spread of the infection.

Explanation

A virus consists of a protein coat (capsid) that surrounds its genetic material (DNA or RNA).

It lacks cellular structures.

It is not considered a complete cell.

Explanation

In an arithmetic progression, the sum of n terms between a and b is given by: Sum = n(a+b)/2

This formula uses the first and last terms to find the total of evenly spaced values.

Explanation

To find the sum, we need to calculate each term:

i^101 = i (since i^1 = i and the powers repeat every 4 terms)

i^102 = i^2 = -1

i^103 = i^3 = -i

i^104 = i^4 = 1

Now, let's add them up:

i + (-1) + (-i) + 1 = 0

Explanation

Conduct management refers specifically to the strategies teachers use to prevent and respond to misbehavior and discipline issues.

It is a subset of classroom management focused on student behavior.

Explanation

The use of "will" here shows willingness to help someone.

It expresses a voluntary action or offer.

Explanation

Listen means سنو

Ignore means نظر انداز کرنا