Explanation

The vector product (cross product) of two vectors gives a vector that is perpendicular to both original vectors.

Angular momentum is a vector product of position and linear momentum vectors.

Explanation

Quaternary

(Haemoglobin has a quaternary structure as it consists of multiple polypeptide chains.)

Explanation

The red one is positive (+), the black one is negative (-).

Never connect the red cable to the negative battery terminal or a vehicle with a dead battery

Explanation

 Zoological/botanical garden is not included under in situ conservation.

Explanation

Numismatics is the study of coins, currency, and medals.

It focusing on their history, usage, and design throughout different civilizations.

Explanation

Explanation

In the borax bead test, cobalt ions (Co²+) react with borax to form cobalt metaborate (Co(BO2)2), which produces a distinct blue color. 

Explanation

Endometriosis is a condition where tissue similar to the lining of the uterus grows outside the uterus.

This tissue can cause pain and infertility, primarily in women.

There is very strong evidence linking endometriosis to female infertility.

Studies show that a significant portion of women with infertility also have endometriosis.

While endometriosis can rarely occur in men, it is not considered a significant cause of infertility in males. 

Explanation

 The proper term for "X" is Plane of symmetry.

A plane of symmetry is an imaginary plane that divides a crystal into two halves, where each half is the mirror image of the other. 

Explanation

 When a sound wave moves from one medium to another, the quantity that remains the same is its frequency. 

The frequency of a sound wave is determined by the source of the sound and doesn't change when it enters a different medium.

However, the wavelength and speed of the wave can change depending on the properties of the new medium.