Explanation

Mega is a unit prefix in metric systems of units denoting a factor of one million (106 or 1000000).

It has the unit symbol M.

It was confirmed for use in the International System of Units (SI) in 1960.

Mega comes from Ancient Greek.

Explanation

Fish: An aquatic animal that lives exclusively in water and breathes using gills. 

Tortoise: A reptile that lives on land, though it can enter water. 

Frog: An amphibian that lives both on land and in water, breathing through lungs and moist skin. 

Therefore, the fish is unique because of its exclusively aquatic habitat

Explanation

Explanation

If a man is facing north and turns left, he will be facing west.

If he turns left again, he will then be facing south. 

Starts: Facing North.

First turn left: From North, a left turn leads to West.

Second turn left: From West, another left turn leads to the South.

Explanation

All others are mammals;

A Snake is a reptile.

Explanation

cos 60° = sin 30°  

cos 60° = 1/2 and sin 30° = 1/2

Explanation

This is a standard trigonometric identity:

cos(90° − ∅) = sin(∅)

It shows the co-function relationship between sine and cosine.

Explanation

In a circle, if a radius (or line from the center) bisects a chord (divides it into two equal parts),

It is perpendicular to that chord. This is a standard geometric property of circles.

Explanation

tandard deviation measures how much the values in a data set vary from the mean.

Given series: 4, 4, 4, 4, 4, 4

- Step 1: Find the mean  

  Mean = (4 + 4 + 4 + 4 + 4 + 4) / 6 = 24 / 6 = 4

- Step 2: Subtract the mean from each value and square it  

  (4−4)² = 0  

  Repeating for all values: 0, 0, 0, 0, 0, 0

- Step 3: Find the average of squared differences  

  (0 + 0 + 0 + 0 + 0 + 0) / 6 = 0

- Step 4: Square root of variance = standard deviation  

  √0 = 0

Explanation

Median of 5, 9, 3, 1, 4, 6:  

Arrange: 1, 3, 4, 5, 6, 9  

Median = average of middle two = (4 + 5)/2 = 4.5