For the following questions answer them individually
Rank of the matrix
$$ A = \begin{bmatrix}1 & 1 & 2 \\1 & 2 & 3 \\ 0 & -1 & 1 \end{bmatrix} $$ is
The value of $$t$$ for which $$A + tB$$ is perpendicular to $$C$$ where $$A = i + 2j + 3k, B = -i + 2j + k$$ and $$C = 3i + j$$
The equation of the plane through the line $$ \frac {x - 1}{3} = \frac {y - 4}{2} = \frac {z - 4}{-2} $$ and parallel to the line $$ \frac {x + 1}{2} = \frac {y - 1}{-4} = \frac {z + 2}{1} $$ is
Let $$E$$ and $$F$$ be any two events with $$4 P(E \cup F) = 0.8, P(E) = 0.4$$ and $$P (E/F) = 0.3$$.Then $$(F)$$ is .
In a class of 45 students, the mean mark of 25 girls is 32 and the mean mark of 20 boys is 27.5. What is the class mean?
If $$ L \left\{ f(t) \right\} = F (s),$$ then the value of $$ L \left\{ e^{-at} f(t) \right\} $$ is