Explanation

Periods in the periodic table are horizontal rows (left to right).

There are 7 periods in total.

Explanation

• Argon (Ar) is a noble gas that is not typically associated with acid rain.

Acid rain is caused by the presence of pollutants in the air, such as:

• Sulfur dioxide (SO2)
• Nitrogen oxides (NOx)
• Oxygen (O2) plays a role in the formation of acid rain, as it reacts with SO2 and NOx to form acidic compounds.

Explanation

Primary Cause of 2022 Floods:

Record Monsoon Rains: Pakistan received 190% more rainfall than average (NDMA data), submerging 1/3 of the country.

Glacial Melt: Heatwaves accelerated melting, adding to water volume (UN report).

Poor Infrastructure: Weak dams, drainage systems, and urban planning worsened flooding.

Explanation

Explanation

• Cytophase is not a stage of mitosis.

The stages of mitosis are:

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase

Explanation

To find the harmonic that is two octaves higher in pitch than the fundamental, we need to consider the frequency multiplication.

One octave higher = 2 × fundamental frequency

Two octaves higher = 2 × 2 × fundamental frequency = 4 × fundamental frequency

The fourth harmonic has a frequency four times the fundamental frequency, which corresponds to two octaves higher.

Explanation

Explanation

Explanation

Explanation

A reflecting telescope uses two mirrors:

1. The primary mirror (which collects and focuses light).
2. The secondary mirror (which directs the focused light to the eyepiece), to form an image of distant objects.