Could the number of eggs of young ones by an oviparous and a viviparous mother be equal? Why?

Give reasons for the following: a. Compared to internal fertilization the external fertilization is disadvantageous to the animal. b. Chances of survival of young ones are more in vivparous than in oviparous.

Give reasons for the following: Chances of survival of young ones are more in viviparous animals than in oviparous animals.

A coin is tossed 2 n times. The chance that the number of times one gets head is not equal to the number of times one gets tail is

A die has six faces numbered from 1 to 6. It is rolled and the number on the top face is noted. When this is treated as a random trial. a) What are the possible outcomes ? b)Are they equally likely? Why? c) Find the probability of a composite number turning up on the top face.

If you could use any sources of energy for heating your food, which one would you use and why?

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels?

There are four balls of different colours and four boxes of colours same as those of the balls. The number of ways in which the balls, one in each box, could be placed such that a ball does not got to box of its own colour own colour , is :

If a bag containing red and white balls, half the number of white balls is equal to one - third the number of red balls. Thrice the total number of balls by 6. How many balls of each colour does the bag contain ?