A character bigram is a pair of two adjacent characters in a string. We need to find the number of distinct bigrams in the string $thoughtsoftheghosts$.
The input string is: $thoughtsoftheghosts$.
We can list all possible adjacent pairs (bigrams) from the string:
Now, let's identify the unique bigrams from the list above. We only count each distinct pair once:
By counting the unique bigrams listed above, we find there are 14 distinct bigrams.
Therefore, the total number of unique character bigrams in the string $thoughtsoftheghosts$ is 14.
$A$ is an ($n \times n$) matrix. Consider the following two statements
Statement 1: Columns of matrix $A$ are linearly independent
Statement 2: Inverse of matrix $A$ exists
Which one of the following statements is TRUE?
A bacterium can be approximated as a cylinder with a hemisphere at each end, as shown in the figure. The cylinder has a height of $1 \mu\text{m}$ and diameter of $1 \mu\text{m}$. Assuming that the density of the bacterium is equal to that of water, what is the approximate mass of this bacterium?

Given: density of water = $10^3 \text{ kg/m}^3$; $1 \mu\text{m} = 10^{-6}\text{ m}$
Volume of a cylinder = $\pi r^2 h$, where $r$ is the radius and $h$ is the height of the cylinder
Volume of a sphere = $\frac{4}{3} \pi r^3$, where $r$ is the radius of the sphere