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From the given table, the most common mark is 3 with a frequency of 18

Iron (soft iron) is usually preferred to steel in the making of electromagnets because it is more easily magnetized and equally more easily demagnetized than [II, III and IV]

Lenz's law, in electromagnetism, statement that an induced electric current flows in a direction such that the current opposes the change that induced it.

Nuclear Fusion occurs at very high temperature. I.e Thermonuclear reaction.

Radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.

critical angle formula = \(sin^{-1}\) \(\frac{n_2}{n_1}\) → \(sin^{-1}\) \(\frac{1}{1.33}\) = \(sin^{-1}\) 0.7518 = 48.75º

V = \(\frac{s}{t} = \frac{900}{3} = 300\)m\s f = \(\frac{v}{\pi} = \frac{300}{0.30}\) = 1000Hz

Amphoteric oxide reacts with both acid and alkaline and only amphoteric oxide can displace hydrogen from alkaline solution (Al, Pb, Sn and Zn).

You can determine the group of an element by the number of electrons of their outermost shell. Hence; this element silicon belongs to group 5 OR The Group to which an element belongs to, can be identified by adding the number of electrons of the orbital with the highest principal quantum number, in this case, 3s2 and 3p3. Therefore, 2+3 is equal to 5 note; if the highest principal quantum number is just 3s2 for example then the element belong to group 2.

As global warming continues to exacerbate sea level rise and extreme weather, our nation's floodplains are expected to grow.

Benzene undergoes substitution reaction whereby one or more hydrogen atoms on the benzene ring is/are replaced by other atoms or groups of atoms. E.g CH\(_3\), OH, NO\(_2\), NH\(_2\) etc can be substituted to replace hydrogen atom. Substitution reaction is a reaction where one functional group is exchanged for another. There are several types of substitution reactions, including nucleophilic, electrophilic, and free radical. A substitution reaction is more peculiar to benzene compared to an addition reaction; benzene primarily undergoes substitution reactions because addition reactions would disrupt its stable aromatic ring structure, causing it to lose its unique stability due to delocalized electrons.

\theta = 30 x 2(∠ at center twice ∠ at circumference) ∴ \theta = 60^\circ Length of arc = \(\frac{\theta}{360}\times 2\pi r\) = \(\frac{60}{360}\times 2 \times \frac{22}{7}\times \frac{21}{1}\) = 22cm

Locus of a point P(x,y) which is equidistant from Q(0,0) and R(2,1) is the perpendicular bisector of the straight line joining Q and R Mid point QR = \(\frac{x_2 + x_1}{2}, \frac{y_2 + y_1}{2}\) = \(\frac{2 + 0}{2}, \frac{1 + 0}{2}\) = \((1, \frac{1}{2})\) Gradient of QR = \(\frac{y_{2} - y_{1}}{x_{2} - x_{1}}\) = \(\frac{1 - 0}{2 - 0}\) = \(\frac{1}{2}\) Gradient of PM = \(\frac{-1}{\frac{1}{2}}\) = -2 Equation of PM = y - y\(_1\) = m(x-x_\(_1\)) i.e y - 1/2 = -2(x-1) 2y - 1 = -4(x-1) 2y - 1 = -4x + 4 2y + 4x = 5

γ + S = 180(Allied angles) S = 180 - γ α + P = 180(Allied angles) p = 180 - α β = P + S β = 180 - α + 180 - γ β = 360 - α - γ β + α + γ = 360

\theta = 45 x 2 (∠ at center twice ∠ at \theta) \theta = 90^\circ Area of sector = \(\frac{\theta}{360}\) x \pir\(^2\) = \(\frac{90}{360}\) x \(\frac{22}{7}\) x 7 x 7 = \(\frac{77}{2}\)cm\(^2\) Area of triangle = \(\frac{1}{2}\) ab sin \theta = \(\frac{1}{2}\) x 7 x 7 sin 90 = \(\frac{1}{2}\) x 7 x 7 x 1 = \(\frac{49}{2}\) cm\(^{2}\) Area of shaded region = \(\frac{77}{2}\) - \(\frac{49}{2}\) = \(\frac{28}{2}\) = 14cm\(^2\)