A triangle has a base of $10$ cm, measured to the nearest centimetre, and a height of $5.0$ cm, measured to the nearest $0.1$ cm. Find the lower bound for the area of the triangle.

A physical frequency is defined as $f=\frac{1}{t}$. If $t=0.040$ s correct to 2 significant figures, calculate the lower bound of the frequency $f$.

True or False: In a continuous measurement interval $L\le T<U$, if the original value was rounded up to the recorded value, the true value $T$ must have been in the sub-interval $[L,x)$.

Fill in the blank: On a number line representing the interval of a continuous measurement $x$ with lower bound $L$ and upper bound $U$, the limits of accuracy are represented by a _____ point at $L$ and an _____ point at $U$.

True or False: If a length $L$ is measured as $8$ m to the nearest metre, the value $7.5$ m is a possible value for the actual length, but $8.5$ m is not.