Explanation

Given an = n²:

a13 = 13² = 169

a20 = 20² = 400

The sum of the 13th and 20th term is:

169 + 400 = 569

Explanation

'Every' is an indefinite adjective because it refers to each member of a group individually, without specifying a particular one.

It modifies the noun 'creature' in a non-specific way.

Similar examples: each, some, many, few.

Explanation

Ray tracing is the method of following individual light rays from an object to the eye (or camera) to simulate how light interacts with surfaces (e.g., reflection, refraction).

It is widely used in computer graphics, optics, and physics to model light paths accurately.

Explanation

Let's denote the two numbers as 2x and 3x, based on the ratio 2:3.

The difference between the numbers is:

3x - 2x = 60

x = 60

Now, find the numbers:

Smaller number = 2x = 2 × 60 = 120

Larger number = 3x = 3 × 60 = 180

The numbers are 180 and 120.

Explanation

The Intuitive Stage (ages 4–7) is the second part of Piaget’s Pre-operational Stage, where children begin to use primitive reasoning and ask many questions.

They start to move beyond egocentric thought and show improved logical thinking, though still limited compared to later stages.

Explanation

Brainstorming is a group creativity technique where participants suggest ideas freely without immediate criticism.

It encourages divergent thinking, helping generate multiple solutions to a problem quickly.

Explanation

Tetanus spores, found in soil and dust, enter the body through deep wounds or punctures.

In such low-oxygen environments, the bacteria produce toxins that affect muscles and nerves.

Explanation

Laser amplification involves increasing light intensity through stimulated emission inside a resonant optical cavity.

The resonance causes photons to bounce back and forth, stimulating more emissions and amplifying the light.

Explanation

To find the area of the border, let's first find the area of the entire rectangle and the area of the inner rectangle.

Area of entire rectangle = Length × Width

= 20 × 10

= 200 cm²

The inner rectangle's dimensions are:

Length = 20 - 2 × 2 = 16 cm

Width = 10 - 2 × 2 = 6 cm

Area of inner rectangle = 16 × 6

= 96 cm²

Area of border = Area of entire rectangle - Area of inner rectangle

= 200 - 96

= 104 cm²

Explanation

Formal drama involves scripted performances where students follow written texts.

It is controlled by the teacher, with little room for spontaneity.