**Given :** let A , B and C represent the subjects physics,chemistry and mathematics respectively ,

the probability of neelam getting A grade in these three subjects is given i.e ,

P(A) = 0.2 , P(B) = 0.3 and P(C) = 0.9

\(\Rightarrow\) P(\(\overline A\)) = 0.8 , P(\(\overline B\)) = 0.7 and P(\(\overline C\)) = 0.1

To Find:

**(i) **The probability that neelam gets all A grades

Here, P(getting all A grades) = P(A ∩ B ∩ C)

= P(A) x P(B) x P(C)

= 0.2 x 0.3 x 0.9

**Therefore,** The probability that neelam gets all A grades is 0.054.

**(ii) **no A grade

Here , P(getting no A grade) = P(\(\overline A\cap \overline B \,\cap \overline C\))

**Therefore, **The probability that neelam gets no A grade is 0.056.

**(iii) **excatly 2 a grades

P(getting excatly 2 A grades)

= P(A and B and not c) + P (B and C and not A) + P (C and A and not B)

**Therefore, **The probability that neelam gets excatly 2 A grades is 0.348.