The approximate value of $\sqrt{63}$ is

If there is an error of $\pm 0.04 \text{ cm}$ in the measurement of the diameter of a sphere,then the approximate percentage error in its volume,when the radius is $10 \text{ cm}$,is

The radius and the height of a right circular solid cone are measured as $7 \text{ ft}$ each. If there is an error of $0.002 \text{ ft}$ for every foot in measuring them,then the error in the total surface area of the cone (in $\text{sq. ft}$) is:

The approximate value of $f(x)=3x^{2}+5x+3$ at $x=3.02$ is

The time $T$ of oscillation of a simple pendulum of length $L$ is governed by $T=2 \pi \sqrt{\frac{L}{g}}$,where $g$ is constant. The percentage by which the length must be changed in order to correct an error of loss equal to $2$ minutes of time per day is

An equilateral triangle has a side of $10$ units. If an error of $0.05$ units is made in measuring the side, then the percentage error in the area of the triangle is: