Questions

Atomic weight=number of neutrons+number of protons

Heritable variation is one of the four most important factors that affect whether natural selection can occur. These factors include

1) Heritable variation

2) Descent with modification

3) Struggle for survival, and necessarily if the others are satisfied

4) Survival of the fittest.

Heritable variation allows for possibly beneficial, negative, or even neutral mutations to get filtered during each generation by natural selection--weeding out negative mutations, passing on positive and neutral ones. Without heritable variation, species would quickly fall victim to parasites who take advantage of identical genetic material in a population and evolution would not occur.

Variation is the raw material of evolution.

90 D in RA means 90 Degrees in Right Angle. It is a logic question which is to be eloborated.

Some more of its kind are:

1. 52 W in a Y     -    52 Weeks in a Year

2. 7 C in a R        -    7 Colours in a Rainbow

3. 9 P in SS

4. 5 C in an OF

5. 12 S of the Z

I = Prt

Yes, the ability to do work is called Energy is True.

The ball with which Table Tennis is played is called Ping Pong Ball.

According to the International rules, the diameter of the ping pong ball must be not less than 39.5 millimeters and not greater than 40.5  millimeters having a mass of 2.7 grams.